WO2016132659A1 - Wireless communication system, wireless communication device, and wireless communication method - Google Patents

Wireless communication system, wireless communication device, and wireless communication method Download PDF

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Publication number
WO2016132659A1
WO2016132659A1 PCT/JP2016/000020 JP2016000020W WO2016132659A1 WO 2016132659 A1 WO2016132659 A1 WO 2016132659A1 JP 2016000020 W JP2016000020 W JP 2016000020W WO 2016132659 A1 WO2016132659 A1 WO 2016132659A1
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WIPO (PCT)
Prior art keywords
wireless communication
active
wireless
communication device
failure
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PCT/JP2016/000020
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French (fr)
Japanese (ja)
Inventor
悟史 園部
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日本電気株式会社
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Application filed by 日本電気株式会社 filed Critical 日本電気株式会社
Priority to US15/547,542 priority Critical patent/US10484896B2/en
Publication of WO2016132659A1 publication Critical patent/WO2016132659A1/en

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/04—Arrangements for maintaining operational condition
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/74—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission for increasing reliability, e.g. using redundant or spare channels or apparatus
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/22—Arrangements for detecting or preventing errors in the information received using redundant apparatus to increase reliability
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
    • H04L41/06—Management of faults, events, alarms or notifications
    • H04L41/0654—Management of faults, events, alarms or notifications using network fault recovery
    • H04L41/0668—Management of faults, events, alarms or notifications using network fault recovery by dynamic selection of recovery network elements, e.g. replacement by the most appropriate element after failure
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L69/00—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass
    • H04L69/40—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection

Definitions

  • the present invention relates to a wireless communication system, a wireless communication apparatus, and a wireless communication method, and more particularly to a wireless communication system, a wireless communication apparatus, and a wireless communication method in which two wireless communication apparatuses are configured redundantly.
  • Some wireless communication systems that require high communication quality include a wireless communication device having a redundant configuration in order to prevent packet loss and packet delay from occurring when a failure occurs in the wireless communication device.
  • Patent Document 1 discloses a technique in which two wireless communication devices are configured redundantly.
  • two wireless communication devices are connected to a selection device, and a switch control unit in the selection device uses one of them depending on the failure occurrence status of the two wireless communication devices.
  • the switch control unit in the selection device receives the failure information and switches the current spare device to the current device.
  • a switch control unit that performs switching control of active backups of two wireless communication devices is provided as a dedicated controller inside a selection device outside the wireless communication device. Therefore, there is a problem that a simple system configuration cannot be achieved and a problem that the cost of the entire system becomes high. In addition, there is a mounting problem such as the need to place a wireless communication device near a selection device with a controller. Accordingly, one of the objects of the present invention is to solve the above-described problems, and a wireless communication system capable of switching a working standby between two wireless communication apparatuses without providing a dedicated controller outside the wireless communication apparatus.
  • a wireless communication apparatus and a wireless communication method are provided.
  • the wireless communication system is arranged in such a manner that the first and second wireless communication apparatuses that are the active system or the standby system are disposed opposite to the first and second wireless communication apparatuses via a wireless line. And third and fourth wireless communication apparatuses serving as a system or a standby system. Each of the first to fourth wireless communication apparatuses is based on a failure occurrence state of an active wireless communication apparatus on the opposite side facing the own apparatus through the wireless line in a situation where the own apparatus is an active system.
  • the switching instruction for instructing the wireless communication device to be the active system on the opposite side is transmitted to the active wireless communication device on the opposite side and the standby wireless communication device, and received from the wireless communication device on the opposite side Based on the switching instruction, the own apparatus is set to the active system or the standby system.
  • the first wireless communication device is a wireless communication device that is configured redundantly with another wireless communication device and becomes an active or standby system.
  • the radio communication apparatus is configured to be connected to the active system on the opposite side based on the failure occurrence state of the active radio communication apparatus on the opposite side facing the own apparatus via a wireless line.
  • the switching control unit determines the switching instruction that instructs the wireless communication device that is to be the working system on the facing side.
  • a wireless transmission unit that transmits to the active and standby wireless communication devices, and a wireless reception unit that receives the switching instruction from the opposite active wireless communication device. Then, the switching control unit sets the own apparatus as an active system or a standby system based on the switching instruction received from the opposite-side active wireless communication apparatus.
  • the second wireless communication device is a wireless communication device that is configured redundantly with another wireless communication device, becomes an active system or a standby system, and transmits a signal via a wireless line.
  • the wireless communication apparatus detects a failure occurrence state of the active wireless communication apparatus on the opposite side facing the own apparatus via the wireless line, and based on the failure occurrence state
  • a switching control unit that determines a wireless communication device to be used on the opposite side, and a wireless transmission unit that transmits a signal indicating the determined wireless communication device via the wireless line.
  • the first wireless communication method is a wireless communication method using a wireless communication system.
  • This wireless communication method is arranged such that the first and second wireless communication apparatuses that are the active system or the standby system, and the first and second wireless communication apparatuses are opposed to each other via a wireless line, and the active system or the standby system. And third and fourth wireless communication apparatuses serving as systems.
  • a switching instruction for instructing the wireless communication device to be the active system is transmitted to the active and standby wireless communication devices on the opposite side, and each of the first to fourth wireless communication devices is transmitted.
  • the own device is set as the active or standby system.
  • the second wireless communication method is configured to be redundant with other wireless communication devices, and is a wireless communication method using a wireless communication device that is an active system or a standby system, and in a situation where the own device is an active system.
  • a switching instruction for instructing the wireless communication device serving as the active system on the opposite side Based on the switching instruction transmitted to the active wireless communication apparatus on the opposite side and received from the active wireless communication apparatus on the opposite side, the own apparatus is set as the active or standby system.
  • FIG. 1 is a diagram illustrating a configuration example of a wireless communication system according to a first embodiment.
  • 1 is a diagram illustrating a configuration example of a wireless communication device according to a first embodiment.
  • 6 is a diagram illustrating a configuration example of a wireless communication system according to a second embodiment.
  • FIG. 6 is a diagram illustrating a configuration example of a wireless communication device according to a second embodiment.
  • FIG. 9 is a sequence diagram illustrating an example of an operation when a failure occurs in a wireless transmission unit of an active wireless communication device in a wireless communication system according to a second embodiment.
  • FIG. 9 is a diagram illustrating an example of an operation when a failure occurs in a wireless transmission unit of an active wireless communication device in a wireless communication system according to a second embodiment.
  • FIG. 10 is a sequence diagram illustrating an example of an operation when a failure occurs in a wireless reception unit of an active wireless communication device in a wireless communication system according to a second embodiment.
  • FIG. 10 is a diagram illustrating an example of an operation when a failure occurs in a wireless reception unit of an active wireless communication device in a wireless communication system according to a second embodiment.
  • FIG. 10 is a sequence diagram illustrating an example of an operation when a failure occurs in a wireless line in the wireless communication system according to the second embodiment.
  • FIG. 10 is a sequence diagram illustrating an example of an operation when a failure occurs in a wireless line in the wireless communication system according to the second embodiment.
  • FIG. 10 is a sequence diagram illustrating an example of an operation when a failure occurs in a wireless line in the wireless communication system according to the second embodiment.
  • FIG. 10 is a diagram illustrating an example of an operation when a failure occurs in a wireless line in the wireless communication system according to the second embodiment.
  • FIG. 6 is a diagram illustrating an example of a transmission timing of a radio frame of each radio communication device when a fault occurs on a radio line in the radio communication system according to the second embodiment.
  • FIG. 10 is a flowchart illustrating an example of an operation when the wireless communication apparatus according to the second embodiment is an active system.
  • FIG. 10 is a flowchart illustrating an example of an operation when the wireless communication apparatus according to the second embodiment is a standby system.
  • FIG. 1 shows a configuration example of a wireless communication system according to this embodiment.
  • the wireless communication system shown in FIG. 1 is arranged with a redundant configuration of wireless communication devices 10A and 10B serving as a working system or a standby system, and facing the wireless communication devices 10A and 10B via a wireless line.
  • redundantly configured wireless communication apparatuses 10C and 10D serving as standby systems.
  • the wireless communication devices 10A to 10D are not specified, they are appropriately referred to as the wireless communication device 10.
  • a wireless communication device 10 that faces the device itself via a wireless line when viewed from a certain wireless communication device 10 is referred to as a wireless communication device 10 on the opposite side.
  • the radio communication devices 10A to 10D have a radio communication function for performing radio communication with the radio communication device 10 on the opposite side.
  • the wireless communication devices 10A to 10D transmit and receive wireless signals in a situation where the own device is an active system. On the other hand, in a situation where the wireless communication devices 10A to 10D are in a standby system, the wireless communication devices 10A to 10D stop transmitting wireless signals (wireless mute state) and only receive wireless signals.
  • the wireless communication devices 10A to 10D transmit and receive wireless signals using the same frequency regardless of whether the wireless communication devices 10A to 10D are active or standby.
  • the active wireless communication device 10 wireless communication devices 10A and 10C in FIG. 1
  • the standby wireless communication device 10 wireless communication devices 10B and 10D in FIG. 1
  • FIGS. 2 to 4, FIG. 6, FIG. 8, and FIG. 11 The same applies to FIGS. 2 to 4, FIG. 6, FIG. 8, and FIG. 11).
  • FIG. 2 shows a configuration example of the wireless communication device 10A according to the present embodiment.
  • the configurations of the wireless communication devices 10B to 10D are the same as the configuration of the wireless communication device 10A.
  • the radio communication device 10A illustrated in FIG. 2 includes a radio transmission unit 101 that receives radio signals from the radio communication devices 10C and 10D on the opposite side, and a radio reception that transmits radio signals to the radio communication devices 10C and 10D on the opposite side.
  • Unit 102 and a switching control unit 103 that controls switching of the active backup of the wireless communication device 10A.
  • the switching control unit 103 detects a failure occurrence state of the active wireless communication device 10 among the opposing wireless communication devices 10C and 10D, and the detected failure occurrence state Based on the above, the wireless communication device 10 to be the active system is determined on the opposite side.
  • the wireless transmission unit 101 transmits a wireless signal indicating the active wireless communication device 10 on the opposite side to the active and standby wireless communication devices 10 on the opposite side. It is assumed that this wireless signal is transmitted to the opposite side as a switching instruction for instructing the wireless communication device 10 that is the active system on the opposite side.
  • the switching control unit 103 confirms the wireless communication apparatus 10 instructed by the switching instruction, and performs wireless communication based on the confirmation result.
  • the apparatus 10A is assumed to be an active system or a standby system. Specifically, when the wireless communication device 10A is instructed in a situation where the wireless communication device 10A is the active system, the switching control unit 103 leaves the wireless communication device 10A as the active system and the wireless communication device 10B instructs If so, the wireless communication device 10A is switched from the active system to the standby system.
  • the switching control unit 103 switches the wireless communication device 10A from the standby system to the active system, and the wireless communication device 10B is instructed. In this case, the wireless communication device 10A remains in the standby system.
  • the wireless communication devices 10A to 10D are active on the opposite side based on the failure occurrence status of the opposite-side active wireless communication device 10 in the situation where the own device is the active system.
  • a switching instruction for instructing the wireless communication device 10 to be the system is transmitted to the active and standby wireless communication devices 10 on the opposite side.
  • the wireless communication devices 10A to 10D set their own device as the active system or the standby system based on the switching instruction received from the active wireless communication device 10 on the opposite side. Therefore, as in the technique described in Patent Document 1, there is an effect that it is possible to switch the active standby of the radio communication devices 10A to 10D without providing a dedicated controller outside the radio communication devices 10A to 10D. It is done.
  • FIG. 3 shows a configuration example of the wireless communication system according to the present embodiment.
  • the wireless communication system shown in FIG. 3 is an example when the wireless communication devices 10A to 10D are connected to an optical line as a wired network.
  • the wireless communication system shown in FIG. 3 is different from the wireless communication system shown in FIG. 1 in that an L2SW (Layer 2 switch) 21, optical couplers 31 and 32, and a hybrid 41 are provided on the wireless communication devices 10A and 10B side.
  • an L2SW 22, optical couplers 33 and 34, and a hybrid 42 are added to the wireless communication devices 10C and 10D.
  • the L2SWs 21 and 22 are connected to an optical line, and receive and transmit optical signals.
  • the optical couplers 31 to 34 branch and combine optical signals.
  • the hybrids 41 and 42 branch and combine radio signals.
  • the wireless communication devices 10A to 10D have not only a wireless communication function but also an optical communication function.
  • the wireless communication devices 10A to 10D transmit and receive wireless signals and optical signals when the own device is an active system. On the other hand, when the wireless communication devices 10A to 10D are the standby system, the wireless communication devices 10A to 10D stop transmitting the wireless signal and the optical signal (wireless mute state, optical mute state), and only receive the wireless signal and the optical signal. .
  • the wireless communication devices 10A to 10D transmit and receive wireless signals using the same frequency regardless of whether the wireless communication devices 10A to 10D are active or standby.
  • FIG. 3 regarding the signal lines between the constituent elements, the signal lines in a communicable state are indicated by solid lines, and the mute state signal lines are indicated by dotted lines (hereinafter, FIG. 4, FIG. 6, FIG. 8). And the same in FIG. 11).
  • FIG. 4 shows a configuration example of the wireless communication device 10A according to the present embodiment.
  • the configurations of the wireless communication devices 10B to 10D are the same as the configuration of the wireless communication device 10A. 4 adds an optical receiver 104, a radio frame multiplexer 105, a radio frame extractor 106, and an optical transmitter 107 to the radio communication device 10A shown in FIG. is doing.
  • the optical receiving unit 104 receives an optical signal from the optical line via the optical coupler 31.
  • the radio frame multiplexing unit 105 replaces the data included in the optical signal from the optical receiving unit 104 with the radio frame, and instructs the radio communication device 10 to be the active system on the opposite side.
  • the switching instruction to be multiplexed is multiplexed on the radio frame.
  • the device ID (IDentifier) of the wireless communication device 10 serving as the active system is multiplexed as the switching instruction.
  • the radio transmission unit 101 transmits the radio frame from the radio frame multiplexing unit 105 to the active and standby radio communication devices 10 on the opposite side.
  • the wireless transmission unit 101 stops transmission of a wireless frame under the control of the switching control unit 103.
  • the wireless receiving unit 102 receives a wireless frame from the active wireless communication device 10 on the opposite side.
  • the radio frame extraction unit 106 extracts data and a switching instruction from the radio frame from the radio reception unit 102.
  • the optical transmission unit 107 replaces the data from the wireless frame extraction unit 106 with an optical signal and transmits it to the optical line via the optical coupler 32. Note that when the wireless communication device 10 ⁇ / b> A is a standby system, the optical transmission unit 107 stops the transmission of the optical signal under the control of the switching control unit 103.
  • the switching control unit 103 performs the wireless reception unit of the wireless communication device 10A.
  • the radio frame multiplexing unit 105 is caused to generate an RDI (Remote Defect Indication) frame as a radio frame.
  • RDI Remote Defect Indication
  • a failure occurrence alarm can be notified to the active and standby radio communication apparatuses 10 on the opposite side.
  • a radio frame transmitted at normal time is referred to as a normal radio frame.
  • the failure detection may be performed by the switching control unit 103 itself, or may be performed by a failure detection unit (not shown) provided in the wireless communication device 10A.
  • the switching control unit 103 changes the active wireless communication device 10 on the opposite side based on the failure occurrence state of the active wireless communication device 10 on the opposite side.
  • the wireless frame multiplexing unit 105 multiplexes the determined device ID of the wireless communication device 10 into the wireless frame. For example, in the initial state, the wireless communication device 10 that is preset by default among the opposite-side wireless communication devices 10C and 10D is determined as the active system, and a failure occurs in the active wireless communication device 10. If the wireless communication device 10 is not restored within a certain period of time, the wireless communication device 10 that is a standby system at that time may be determined as the active system.
  • the switching control unit 103 when receiving the radio frame from the active wireless communication device 10 on the opposite side, the switching control unit 103 confirms the device ID multiplexed in the wireless frame, and determines the wireless communication device 10A based on the confirmation result. The working system or standby system. Specifically, when the wireless communication device 10A is instructed in a situation where the wireless communication device 10A is the active system, the switching control unit 103 leaves the wireless communication device 10A as the active system and the wireless communication device 10B instructs If so, the wireless communication device 10A is switched from the active system to the standby system.
  • the switching control unit 103 switches the wireless communication device 10A from the standby system to the active system, and the wireless communication device 10B is instructed. In this case, the wireless communication device 10A remains in the standby system.
  • the switching control unit 103 uses the active wireless communication device 10A based on the device ID multiplexed in the wireless frame. Switch spares.
  • the switching control unit 103 detects that a failure has occurred in the wireless line, in a situation where the wireless communication device 10A is the active system, the switching control unit 103 leaves the wireless communication device 10A as the active system and the wireless communication device 10A In the situation of the standby system, the radio communication device 10A is switched to the active system. The same applies to the wireless communication device 10B.
  • the wireless communication devices 10A and 10B transition to the both-system active state where both are active. Thereafter, when the failure of the wireless line is recovered and the wireless frame can be received from the active wireless communication device 10 on the opposite side, the switching control unit 103 is based on the device ID multiplexed in the wireless frame. Thus, the active backup of the wireless communication device 10A is switched. As a result, one of the wireless communication devices 10A and 10B becomes a standby system, and the active state of both systems is eliminated.
  • FIG. 5 and FIG. 6 An example of an operation when a failure occurs in the wireless transmission unit 101 of the active wireless communication apparatus 10A in a situation where the system and the wireless communication apparatuses 10B and 10D are standby systems will be described.
  • the same steps are denoted by the same reference numerals.
  • the wireless communication devices 10A to 10D are indicated by a solid line in the active system state, and are indicated by a broken line in the standby system state (in FIGS. 7, 9, and 10 below). the same).
  • FIG. 6 the characters attached to the normal radio frame and the RDI frame indicate the device IDs multiplexed in those radio frames (the same applies to FIGS. 8 and 11 below).
  • the device IDs of the wireless communication devices 10A, 10B, 10C, and 10D are A, B, C, and D, respectively (the same applies to FIGS. 7 to 12 below).
  • wireless frames are constantly transmitted and received between the wireless communication devices 10A and 10B and the wireless communication devices 10C and 10D even when there is no data from the L2SWs 21 and 22.
  • the wireless transmission unit 101 of the current working wireless communication device 10 ⁇ / b> A is normally configured by multiplexing the device ID “C” of the current working wireless communication device 10 ⁇ / b> C on the opposite side.
  • the wireless frame is transmitted to the opposite wireless communication devices 10C and 10D (step S101).
  • a failure has occurred in the wireless transmission unit 101 of the wireless communication device 10A, and the normal wireless frame transmitted from the wireless communication device 10A in step S101 does not reach the wireless communication devices 10C and 10D.
  • Each switching control unit 13 of the wireless communication devices 10C and 10D has passed a preset time since the last reception of the wireless frame from the wireless communication device 10A, and a failure has occurred in the wireless reception unit 102 of the own device. If there is no failure, it is detected that a failure has occurred in the wireless transmission unit 101 of the active wireless communication device 10A on the opposite side (step S102). Therefore, the wireless transmission unit 101 of the active wireless communication device 10C transmits an RDI frame for notifying the occurrence of a failure in the downlink direction to the opposite wireless communication devices 10A and 10B (step S103).
  • the device ID multiplexed in the RDI frame is left as the device ID “A” of the current working wireless communication device 10A on the opposite side.
  • each switching control unit 13 of the wireless communication devices 10A and 10B When receiving the RDI frame from the opposite-side active wireless communication device 10C, each switching control unit 13 of the wireless communication devices 10A and 10B confirms the device ID multiplexed in the RDI frame (step S104). Here, since the device ID “A” of the current active wireless communication device 10A is multiplexed, each switching control unit 13 of the wireless communication devices 10A and 10B does not switch the active backup.
  • the switching control unit 13 of the wireless communication device 10C detects whether the failure has been recovered within a predetermined time T1 after detecting the failure of the wireless transmission unit 101 of the opposite-side active wireless communication device 10A. to decide.
  • the switching control unit 13 of the wireless communication device 10C determines to switch the opposite working system from the wireless communication device 10A to the wireless communication device 10B.
  • the switching control unit 13 of the wireless communication device 10C changes the device ID multiplexed in the RDI frame to the device ID “B” of the wireless communication device 10B (step S105), and the wireless transmission unit 101 of the wireless communication device 10C
  • the RDI frame is transmitted to the radio communication apparatuses 10A and 10B on the opposite side (step S106).
  • the switching control unit 13 of the wireless communication devices 10A and 10B confirms the device ID multiplexed in the RDI frame (step S107).
  • the device ID “B” of the current standby wireless communication device 10B is multiplexed. Therefore, the switching control unit 13 of the wireless communication device 10A switches its own device to the standby system, and the switching control unit 13 of the wireless communication device 10B switches its own device to the working system (step S108).
  • the wireless communication device 10A when a failure occurs in the wireless transmission unit 101 of the active wireless communication device 10A, the wireless communication device 10A can be switched to the standby system, and the wireless communication device 10B can be switched to the active system.
  • the wireless communication apparatuses 10A and 10C are the active system, and the wireless communication apparatuses 10B and 10D are the standby system.
  • the wireless transmission unit 101 of the current working wireless communication device 10C is normally configured by multiplexing the device ID “A” of the current working wireless communication device 10A on the opposite side.
  • the wireless frame is transmitted to the opposite wireless communication devices 10A and 10B (step S201).
  • a failure has occurred in the wireless reception unit 102 of the wireless communication device 10A, and the normal wireless frame transmitted from the wireless communication device 10C in step S201 is not received by the wireless communication device 10A.
  • the switch control unit 13 of the wireless communication device 10A detects that a failure has occurred in the wireless reception unit 102 of the wireless communication device 10A (step S202). Then, the wireless transmission unit 101 of the wireless communication device 10A transmits an RDI frame for notifying an alarm of occurrence of a failure in the upstream direction to the wireless communication devices 10C and 10D on the opposite side (step S203).
  • the device ID multiplexed in the RDI frame remains the device ID “C” of the current working wireless communication device 10C on the opposite side.
  • each switching control unit 103 of the wireless communication devices 10C and 10D confirms the device ID multiplexed in the RDI frame (step S204).
  • each switching control unit 103 of the wireless communication devices 10C and 10D does not switch the active backup.
  • the switching control unit 103 of the wireless communication device 10C has recovered from a failure within a predetermined time T2 (T2 ⁇ T1) after receiving the RDI frame from the active wireless communication device 10A on the opposite side. It is determined whether or not a normal radio frame indicating this is received. Here, it is assumed that there is no restoration within a certain time T2. Therefore, the switching control unit 103 of the wireless communication device 10C determines to switch the opposite active system from the wireless communication device 10A to the wireless communication device 10B.
  • the switching control unit 103 of the wireless communication device 10C changes the device ID multiplexed in the normal wireless frame to the device ID “B” of the wireless communication device 10B (step S205), and the wireless transmission unit 101 of the wireless communication device 10C
  • the normal radio frame is transmitted to the opposite radio communication apparatuses 10A and 10B (step S206).
  • the switching control unit 103 of the wireless communication device 10B receives the normal wireless frame from the active wireless communication device 10C on the opposite side, it checks the device ID multiplexed in the normal wireless frame (step S207).
  • the switching control unit 103 of the wireless communication device 10B switches the own device to the active system (step S208).
  • the switching control unit 103 of the wireless communication device 10A switches the own device to the standby system after elapse of a preset time after detecting that a failure has occurred in the wireless receiving unit 102 of the own device (step S209).
  • the timing at which the radio communication device 10A switches to the standby system is arbitrary, and may be, for example, the timing immediately after the occurrence of a failure in the radio reception unit 102 is detected.
  • the wireless communication device 10A when a failure occurs in the wireless reception unit 102 of the active wireless communication device 10A, the wireless communication device 10A can be switched to the standby system, and the wireless communication device 10B can be switched to the active system.
  • FIG. 9 to FIG. 11 show an example of the operation when a failure occurs in the radio line in a situation where the radio communication devices 10A and 10C are the active system and the radio communication devices 10B and 10D are the standby system.
  • 9 and 10 show that the process of FIG. 10 is performed subsequent to the process of FIG. 9, and step S315 in FIGS. 9 and 10 indicates the same step.
  • the wireless transmission unit 101 of the current working wireless communication device 10A is a normal one in which the device ID “C” of the current working wireless communication device 10C on the opposite side is multiplexed.
  • the wireless frame is transmitted to the opposite wireless communication devices 10C and 10D (step S301).
  • the wireless transmission unit 101 of the current working wireless communication device 10C transmits the normal wireless frame in which the device ID “A” of the current working wireless communication device 10A on the opposite side is multiplexed to the wireless communication on the opposite side. It transmits to apparatus 10A, 10B (step S302).
  • the normal wireless frame transmitted from the wireless communication device 10A in step S301 does not reach the wireless communication devices 10C and 10D.
  • the normal radio frame transmitted from the radio communication device 10C in step S302 does not reach the radio communication devices 10A and 10B.
  • each switching control unit 103 of the wireless communication devices 10A to 10D determines whether or not the failure has been recovered within a predetermined time T3 (T2 ⁇ T1 ⁇ T3) after detecting the failure of the wireless line (T2 ⁇ T1 ⁇ T3). Steps S305 and S306).
  • T3 a predetermined time
  • T3 a predetermined time
  • T3 a predetermined time
  • each wireless transmission unit 101 of the wireless communication devices 10A and 10B transmits an RDI frame to the opposite wireless communication devices 10C and 10D (steps S309 and S310).
  • the device ID multiplexed in the RDI frame can be set in advance.
  • the device ID “C” of the wireless communication device 10C that was the active system before the failure occurred on the opposite side is multiplexed here.
  • each of the wireless transmission units 101 of the wireless communication devices 10C and 10D transmits an RDI frame to the opposite wireless communication devices 10A and 10B (steps S311 and S312).
  • the device ID multiplexed in the RDI frame can be set in advance, and here, the device ID “A” of the wireless communication device 10A that was the active system before the failure occurred on the opposite side is multiplexed here.
  • the device ID “A” of the wireless communication device 10A that was the active system before the failure occurred on the opposite side is multiplexed here.
  • the wireless communication devices 10A and 10B both transmit RDI frames.
  • the frame does not reach the radio communication devices 10C and 10D on the opposite side. Therefore, the RDI frame arrives at the opposite radio communication apparatuses 10C and 10D only after the failure of the radio line is recovered.
  • the RDI frames collide if the transmission timings at which the wireless communication devices 10A and 10B transmit the RDI frame are the same. As a result, neither RDI frame arrives at the opposite radio communication apparatuses 10C and 10D.
  • the wireless communication devices 10C and 10D cannot receive the RDI frame and cannot determine which is the active system, so that both systems remain in the active state. . Further, even when the RDI frame is switched to the normal radio frame when the failure of the radio line is recovered, the normal radio frames may collide with each other. Similar problems can occur in upstream communications.
  • an active system determination sequence is executed.
  • the wireless frame transmission timings in the wireless communication apparatuses 10A and 10B that are in the working system are determined in advance so that the wireless communication apparatuses 10A and 10B alternately transmit the wireless frames.
  • the transmission timing of the radio frame in the radio communication devices 10C and 10D that are in the active system is determined in advance so that the radio communication devices 10C and 10D transmit radio frames alternately.
  • FIG. 12 shows an example of radio frame transmission timing.
  • the characters on the time axis indicate the device ID of the wireless communication device 10 that is transmitting at that time. Referring to FIG.
  • the wireless communication device 10A that was the active system at the time of occurrence of the failure of the wireless line is set as the active system for a preset time after the occurrence of the failure.
  • the radio frame transmits a normal radio frame before the occurrence of a failure and an RDI frame after the occurrence of the failure. If the failure of the wireless line is not recovered within a predetermined time T3 set in advance from the occurrence of the failure, the wireless communication device 10B also becomes the active system. Therefore, the radio communication devices 10A and 10B both transmit RDI frames.
  • the radio communication devices 10A and 10B since the radio frame transmission timings of the radio communication devices 10A and 10B are determined in advance, the radio communication devices 10A and 10B alternately transmit RDI frames. Then, when the failure of the wireless line is recovered thereafter, since the RDI frame of the wireless communication device 10A is transmitted at that time, the RDI frame is received by the opposite wireless communication devices 10C and 10D, The wireless communication device 10C with the device ID “C” multiplexed in the RDI frame continues the active system, and the other wireless communication device 10D switches to the standby system. Thus, by determining the transmission timings of the radio communication devices 10A and 10B in advance, it is possible to avoid collision between RDI frames (or normal radio frames) from the radio communication devices 10A and 10B after the failure recovery. The radio frame transmission timing in the radio communication devices 10C and 10D is the same.
  • the wireless transmission units 101 of the wireless communication devices 10A and 10B alternately transmit RDI frames in steps S309 and S310. For this reason, it is avoided that the RDI frames transmitted by the wireless communication devices 10A and 10B collide after the failure of the wireless line is restored, and the RDI frame transmitted immediately after the recovery is first sent to the opposite wireless communication devices 10C and 10D. Received. Similarly, the wireless transmission units 101 of the wireless communication devices 10C and 10D alternately transmit RDI frames in steps S311 and S312.
  • each switching control unit 103 of the wireless communication devices 10C and 10D confirms the device ID multiplexed in the RDI frame (step S314).
  • the switching control unit 103 of the wireless communication device 10D switches the own device to the standby system (step S315). As a result, the active state of both systems on the wireless communication devices 10C and 10D side is canceled. Therefore, thereafter, only the radio communication device 10C transmits the normal radio frame switched from the RDI frame to the radio communication devices 10A and 10B (step S316).
  • each switching control unit 103 of the wireless communication devices 10A and 10B confirms the device ID multiplexed in the normal wireless frame (step S317).
  • the switching control unit 103 of the wireless communication device 10B switches the own device to the standby system (step S318). As a result, the active status of both systems is canceled on the wireless communication devices 10A and 10B side.
  • both the wireless communication devices 10A and 10B and the wireless communication devices 10C and 10D transition to the active state of both systems, but avoid collision between wireless frames after failure recovery. Therefore, the radio frame can be received on the opposite side, and the active status of both systems can be eliminated.
  • FIG. 13 shows an example of operation when the radio communication device 10 is an active system.
  • the switching control unit 103 determines whether the occurrence of a radio failure is detected (step S401).
  • the wireless failure refers to a failure of the wireless transmission unit 101 of the active wireless communication device 10 on the opposite side, a failure of the wireless reception unit 102 of the own device, and a failure of the wireless line (the same applies to FIG. 14 below). If a wireless failure is detected in step S401 (Yes in step S401), the wireless transmission unit 101 transmits an RDI frame to the opposite-side active and standby wireless communication devices 10 (step S402).
  • the switching control unit 103 determines whether the wireless failure has been recovered within a predetermined time T1 after detecting the occurrence of the wireless failure (step S403). In step S403, when the wireless failure is recovered within the predetermined time T1 (No in step S403), the switching control unit 103 keeps its own device as the active system (step S408).
  • the switching control unit 103 sets the device ID multiplexed in the RDI frame as a standby system before the failure occurs on the opposite side.
  • the wireless transmission unit 101 transmits the RDI frame to the active and standby wireless communication devices 10 on the opposite side (step S404).
  • the switching control unit 103 determines whether or not the wireless failure has been recovered within a preset time T3 (T1 ⁇ T3) after detecting the occurrence of the wireless failure (step S405).
  • step S405 when the wireless failure is recovered within a predetermined time T3 (No in step S405), the wireless transmission unit 101 transmits a normal wireless frame to the active and standby wireless communication apparatuses 10 on the opposite side. At this time, if the RDI frame transmitted in step S404 can be received on the opposite side, the active wireless communication device 10 has been switched (step S407). On the other hand, if the wireless failure is not recovered within the predetermined time T3 in step S405 (Yes in step S405), the above-described active system determination sequence is performed (step S406).
  • step S401 determines whether an RDI frame is received from the opposite-side active radio communication device 10 (step S409). . If an RDI frame is received in step S409 (Yes in step S409), the switching control unit 103 determines whether the device ID multiplexed in the received RDI frame matches the device ID of the own device (step S409). S410). If the device IDs do not match in step S410 (No in step S410), the switching control unit 103 switches the own device to the standby system (step S415).
  • step S410 if the device IDs match in step S410 (Yes in step S410), the switching control unit 103 detects a radio failure by receiving the RDI frame in step S409, and then sets a predetermined time T2 (T2). It is determined whether the wireless failure has been recovered within ⁇ T1 ⁇ T3) (step S411). In step S411, when the wireless failure is recovered within the predetermined time T2 (No in step S411), the switching control unit 103 keeps its own device as the active system (step S414).
  • the switching control unit 103 sets the device ID multiplexed in the normal wireless frame in the standby system before the failure occurs on the opposite side.
  • the wireless transmission unit 101 transmits the normal wireless frame to the active and standby wireless communication devices 10 on the opposite side (step S412).
  • the active radio communication device 10 is switched (step S413).
  • step S409 the switching control unit 103 determines that the device ID multiplexed in the normal radio frame received from the opposite-side active radio communication device 10 is the own. It is determined whether the device ID matches the device ID (step S416). If the device IDs do not match in step S416 (No in step S416), the switching control unit 103 switches the own device to the standby system (step S418). On the other hand, when the device IDs match in step S416 (Yes in step S416), the switching control unit 103 keeps the own device as the active system (step S417). In step S404, the device ID multiplexed in the RDI frame has been changed. However, if the wireless failure is a failure in the wireless line, the RDI frame in steps S402 and S404 is not received on the opposite side, and the device ID may be left unchanged.
  • FIG. 14 shows an example of the operation in the case where the wireless communication apparatus 10 is a standby system.
  • the switching control unit 103 determines whether the occurrence of a radio failure is detected (step S501).
  • the switching control unit 103 determines whether the radio failure has been recovered within a predetermined time T3 after detecting the radio failure. (Step S502).
  • step S502 when the wireless failure is recovered within the predetermined time T3 (No in step S502), the switching control unit 103 keeps its own device as a standby system (step S504).
  • step S503 when the wireless failure is not recovered within a certain time T3 (Yes in step S502), the above-described active system determination sequence is performed (step S503).
  • step S501 determines whether an RDI frame has been received from the opposite-side active wireless communication device 10 (step S505). .
  • the switching control unit 103 determines whether the device ID multiplexed in the received RDI frame matches the device ID of the own device (step S505). S506). If the device IDs do not match in step S506 (No in step S506), the switching control unit 103 leaves the own device as a standby system (step S508). On the other hand, if the device IDs match in step S506 (Yes in step S506), the own device is switched to the active system (step S507).
  • step S505 determines that the device ID multiplexed in the normal radio frame received from the opposite-side active radio communication device 10 is the own. It is determined whether the device ID matches the device ID (step S509). If the device IDs do not match in step S509 (No in step S509), the switching control unit 103 leaves the own device as a standby system (step S511). On the other hand, if the device IDs match in step S509 (Yes in step S509), the switching control unit 103 switches the own device to the active system (step S510).
  • the radio communication devices 10A to 10D have a failure of the active radio communication device 10 on the opposite side in a situation where the own device is the active system. Based on the state of occurrence, a radio frame in which the device ID of the wireless communication device 10 that is the active system on the opposite side is multiplexed is transmitted to the active and standby wireless communication devices 10 on the opposite side. Then, the radio communication devices 10A to 10D set their own device as the active or standby system based on the device ID multiplexed in the radio frame received from the opposite-side active radio communication device 10.
  • the wireless communication devices 10A and 10B when a failure occurs in the wireless line and the wireless communication devices 10A and 10B are alternately wirelessly transmitted at the transmission timing of the wireless frames of the wireless communication devices 10A and 10B when the state is shifted to the active state of both systems. It is predetermined to transmit the frame. Similarly, the wireless frame transmission timings of the wireless communication devices 10C and 10D are determined in advance so that the wireless communication devices 10C and 10D alternately transmit wireless frames. Therefore, after the failure of the wireless line is recovered, collision between the wireless frames from the wireless communication devices 10A and 10B and collision between the wireless frames from the wireless communication devices 10C and 10D can be avoided, so that the wireless frame can be received on the opposite side. Both systems can be resolved.
  • the wireless communication devices 10A to 10D when the occurrence of a failure is detected, the wireless communication devices 10A to 10D multiplex and transmit the device ID in the RDI frame. Therefore, it is possible to notify the opposite-side radio communication device 10 of an alarm indicating the occurrence of a failure.
  • Wireless communication device 101 Wireless transmission unit 102 Wireless reception unit 103 Switching control unit 104 Optical reception unit 105 Radio frame multiplexing unit 106 Radio frame extraction unit 107 Optical transmission unit 21, 22 L2SW 31-34 Optical coupler 41, 42 Hybrid

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Abstract

A wireless communication device (10) is provided with: a switching control unit (103) which, in a situation where the device itself is an active system, determines a wireless communication device that becomes an active system on the opposite side on the basis of the failure occurrence situation of an opposite-side active system wireless communication device opposite to the device itself via a wireless channel; a wireless transmission unit (101) which, in the situation where the device itself is the active system, transmits a switching indication indicating the wireless communication device determined by the switching control unit (103) to opposite-side active system and standby system wireless communication devices; and a wireless reception unit (102) which receives the switching indication from the opposite-side active system wireless communication device. The switching control unit (103) makes the device itself an active system or a standby system on the basis of the switching indication received from the opposite-side active system wireless communication device.

Description

無線通信システム、無線通信装置、無線通信方法Wireless communication system, wireless communication apparatus, and wireless communication method
　本発明は、無線通信システム、無線通信装置、無線通信方法に関し、特に、２台の無線通信装置を冗長構成にした無線通信システム、無線通信装置、無線通信方法に関する。 The present invention relates to a wireless communication system, a wireless communication apparatus, and a wireless communication method, and more particularly to a wireless communication system, a wireless communication apparatus, and a wireless communication method in which two wireless communication apparatuses are configured redundantly.
　高い通信品質が求められる無線通信システムにおいては、無線通信装置に障害が発生した場合にパケットロスやパケット遅延が発生することを抑えるために、無線通信装置を冗長構成にしたものがある。例えば、特許文献１には、２台の無線通信装置を冗長構成にした技術が開示されている。 Some wireless communication systems that require high communication quality include a wireless communication device having a redundant configuration in order to prevent packet loss and packet delay from occurring when a failure occurs in the wireless communication device. For example, Patent Document 1 discloses a technique in which two wireless communication devices are configured redundantly.
　特許文献１に記載の技術によれば、２台の無線通信装置は選択装置に接続され、選択装置内のスイッチ制御部が、２台の無線通信装置の障害発生状況に応じて、一方を現用機器に、他方を予備機器に切り替える。より具体的には、現用機器に障害が発生した場合、これを対向側の現用機器で検出し、障害情報を無線送信する。対向側の現用機器からの障害情報は、障害が発生した現用機器では受信できないため、予備機器で受信され、予備機器から選択装置に送られる。又は、現用機器の障害は、現用機器自身で検出し、現用機器から選択装置に障害情報が送られる。選択装置内のスイッチ制御部は、障害情報を受けて、現在の予備機器を現用機器に切り替える。 According to the technique described in Patent Literature 1, two wireless communication devices are connected to a selection device, and a switch control unit in the selection device uses one of them depending on the failure occurrence status of the two wireless communication devices. Switch to equipment and the other to spare equipment. More specifically, when a failure occurs in the working device, this is detected by the working device on the opposite side, and the failure information is wirelessly transmitted. The failure information from the working device on the opposite side cannot be received by the working device in which the failure has occurred, so is received by the spare device and sent from the spare device to the selection device. Alternatively, the failure of the active device is detected by the active device itself, and failure information is sent from the active device to the selection device. The switch control unit in the selection device receives the failure information and switches the current spare device to the current device.
国際公開第２０１２／１６０８２６号International Publication No. 2012/160826
　しかし、特許文献１に記載の技術は、無線通信装置の外部の選択装置の内部に、２台の無線通信装置の現用予備の切替制御を行うスイッチ制御部を専用のコントローラとして設けている。そのため、簡易なシステム構成にはできないという問題や、システム全体のコストが高くなるという問題がある。また、コントローラのある選択装置の近くに無線通信装置を配置する必要がある等、実装面の問題もある。
　そこで本発明の目的の１つは、上述した課題を解決し、無線通信装置の外部に専用のコントローラを設けることなく、２台の無線通信装置の現用予備の切替を行うことができる無線通信システム、無線通信装置、無線通信方法を提供することにある。 However, in the technique described in Patent Document 1, a switch control unit that performs switching control of active backups of two wireless communication devices is provided as a dedicated controller inside a selection device outside the wireless communication device. Therefore, there is a problem that a simple system configuration cannot be achieved and a problem that the cost of the entire system becomes high. In addition, there is a mounting problem such as the need to place a wireless communication device near a selection device with a controller.
Accordingly, one of the objects of the present invention is to solve the above-described problems, and a wireless communication system capable of switching a working standby between two wireless communication apparatuses without providing a dedicated controller outside the wireless communication apparatus. A wireless communication apparatus and a wireless communication method are provided.
　一態様において、無線通信システムは、現用系又は予備系となる第１及び第２の無線通信装置と、前記第１及び第２の無線通信装置と無線回線を介して対向して配置され、現用系又は予備系となる第３及び第４の無線通信装置と、を備える。前記第１～第４の無線通信装置の各々は、自装置が現用系である状況では、前記無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況に基づいて、前記対向側で現用系となる無線通信装置を指示する切替指示を前記対向側の現用系及び予備系の無線通信装置に送信し、前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする。 In one aspect, the wireless communication system is arranged in such a manner that the first and second wireless communication apparatuses that are the active system or the standby system are disposed opposite to the first and second wireless communication apparatuses via a wireless line. And third and fourth wireless communication apparatuses serving as a system or a standby system. Each of the first to fourth wireless communication apparatuses is based on a failure occurrence state of an active wireless communication apparatus on the opposite side facing the own apparatus through the wireless line in a situation where the own apparatus is an active system. The switching instruction for instructing the wireless communication device to be the active system on the opposite side is transmitted to the active wireless communication device on the opposite side and the standby wireless communication device, and received from the wireless communication device on the opposite side Based on the switching instruction, the own apparatus is set to the active system or the standby system.
　一態様において、第１の無線通信装置は、他の無線通信装置と冗長に構成され、現用系又は予備系となる無線通信装置である。この無線通信装置は、自装置が現用系である状況では、無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況に基づいて、前記対向側で現用系となる無線通信装置を決定する切替制御部と、自装置が現用系である状況では、前記切替制御部が決定した、前記対向側で現用系となる無線通信装置を指示する切替指示を前記対向側の現用系及び予備系の無線通信装置に送信する無線送信部と、前記対向側の現用系の無線通信装置から前記切替指示を受信する無線受信部と、を備える。そして、前記切替制御部は、前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする。 In one aspect, the first wireless communication device is a wireless communication device that is configured redundantly with another wireless communication device and becomes an active or standby system. In the situation where the own apparatus is an active system, the radio communication apparatus is configured to be connected to the active system on the opposite side based on the failure occurrence state of the active radio communication apparatus on the opposite side facing the own apparatus via a wireless line. In a situation where the switching control unit that determines the wireless communication device to be used and the own device is the working system, the switching control unit determines the switching instruction that instructs the wireless communication device that is to be the working system on the facing side. A wireless transmission unit that transmits to the active and standby wireless communication devices, and a wireless reception unit that receives the switching instruction from the opposite active wireless communication device. Then, the switching control unit sets the own apparatus as an active system or a standby system based on the switching instruction received from the opposite-side active wireless communication apparatus.
　一態様において、第２の無線通信装置は、他の無線通信装置と冗長に構成され、現用系又は予備系となり、無線回線を介して信号を送信する無線通信装置である。この無線通信装置は、自装置が現用系である状況では、前記無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況を検知して前記障害発生状況に基づいて前記対向側で現用系となる無線通信装置を決定する切替制御部と、前記無線回線を介して、前記決定した無線通信装置を示す信号を送信する無線送信部と、を備える。 In one aspect, the second wireless communication device is a wireless communication device that is configured redundantly with another wireless communication device, becomes an active system or a standby system, and transmits a signal via a wireless line. In the situation where the own apparatus is the active system, the wireless communication apparatus detects a failure occurrence state of the active wireless communication apparatus on the opposite side facing the own apparatus via the wireless line, and based on the failure occurrence state A switching control unit that determines a wireless communication device to be used on the opposite side, and a wireless transmission unit that transmits a signal indicating the determined wireless communication device via the wireless line.
　一態様において、第１の無線通信方法は、無線通信システムによる無線通信方法である。この無線通信方法は、現用系又は予備系となる第１及び第２の無線通信装置と、前記第１及び第２の無線通信装置と無線回線を介して対向して配置され、現用系又は予備系となる第３及び第４の無線通信装置と、を設ける。そして、前記第１～第４の無線通信装置の各々が、自装置が現用系である状況では、前記無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況に基づいて、前記対向側で現用系となる無線通信装置を指示する切替指示を前記対向側の現用系及び予備系の無線通信装置に送信し、前記第１～第４の無線通信装置の各々が、前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする。 In one aspect, the first wireless communication method is a wireless communication method using a wireless communication system. This wireless communication method is arranged such that the first and second wireless communication apparatuses that are the active system or the standby system, and the first and second wireless communication apparatuses are opposed to each other via a wireless line, and the active system or the standby system. And third and fourth wireless communication apparatuses serving as systems. Then, in the situation where each of the first to fourth wireless communication apparatuses is the active system, the failure occurrence state of the active wireless communication apparatus on the opposite side facing the own apparatus via the wireless line On the opposite side, a switching instruction for instructing the wireless communication device to be the active system is transmitted to the active and standby wireless communication devices on the opposite side, and each of the first to fourth wireless communication devices is transmitted. However, based on the switching instruction received from the opposite-side active wireless communication device, the own device is set as the active or standby system.
　一態様において、第２の無線通信方法は、他の無線通信装置と冗長に構成され、現用系又は予備系となる無線通信装置による無線通信方法であって、自装置が現用系である状況では、無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況に基づいて、前記対向側で現用系となる無線通信装置を指示する切替指示を前記対向側の現用系及び予備系の無線通信装置に送信し、前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする。 In one aspect, the second wireless communication method is configured to be redundant with other wireless communication devices, and is a wireless communication method using a wireless communication device that is an active system or a standby system, and in a situation where the own device is an active system. Based on the failure occurrence state of the active wireless communication device on the opposite side facing the own device through the wireless line, a switching instruction for instructing the wireless communication device serving as the active system on the opposite side Based on the switching instruction transmitted to the active wireless communication apparatus on the opposite side and received from the active wireless communication apparatus on the opposite side, the own apparatus is set as the active or standby system.
　上述の態様によれば、無線通信装置の外部に専用のコントローラを設けることなく、無線通信装置の現用予備の切替を行うことができるという効果が得られる。 According to the above-described aspect, there is an effect that it is possible to switch the active standby of the wireless communication device without providing a dedicated controller outside the wireless communication device.
実施形態１に係る無線通信システムの構成例を示す図である。1 is a diagram illustrating a configuration example of a wireless communication system according to a first embodiment. 実施形態１に係る無線通信装置の構成例を示す図である。1 is a diagram illustrating a configuration example of a wireless communication device according to a first embodiment. 実施形態２に係る無線通信システムの構成例を示す図である。6 is a diagram illustrating a configuration example of a wireless communication system according to a second embodiment. FIG. 実施形態２に係る無線通信装置の構成例を示す図である。6 is a diagram illustrating a configuration example of a wireless communication device according to a second embodiment. FIG. 実施形態２に係る無線通信システムにおいて、現用系の無線通信装置の無線送信部に障害が発生した場合の動作の一例を示すシーケンス図である。FIG. 9 is a sequence diagram illustrating an example of an operation when a failure occurs in a wireless transmission unit of an active wireless communication device in a wireless communication system according to a second embodiment. 実施形態２に係る無線通信システムにおいて、現用系の無線通信装置の無線送信部に障害が発生した場合の動作の一例を示す図である。FIG. 9 is a diagram illustrating an example of an operation when a failure occurs in a wireless transmission unit of an active wireless communication device in a wireless communication system according to a second embodiment. 実施形態２に係る無線通信システムにおいて、現用系の無線通信装置の無線受信部に障害が発生した場合の動作の一例を示すシーケンス図である。FIG. 10 is a sequence diagram illustrating an example of an operation when a failure occurs in a wireless reception unit of an active wireless communication device in a wireless communication system according to a second embodiment. 実施形態２に係る無線通信システムにおいて、現用系の無線通信装置の無線受信部に障害が発生した場合の動作の一例を示す図である。FIG. 10 is a diagram illustrating an example of an operation when a failure occurs in a wireless reception unit of an active wireless communication device in a wireless communication system according to a second embodiment. 実施形態２に係る無線通信システムにおいて、無線回線に障害が発生した場合の動作の一例を示すシーケンス図である。FIG. 10 is a sequence diagram illustrating an example of an operation when a failure occurs in a wireless line in the wireless communication system according to the second embodiment. 実施形態２に係る無線通信システムにおいて、無線回線に障害が発生した場合の動作の一例を示すシーケンス図である。FIG. 10 is a sequence diagram illustrating an example of an operation when a failure occurs in a wireless line in the wireless communication system according to the second embodiment. 実施形態２に係る無線通信システムにおいて、無線回線に障害が発生した場合の動作の一例を示す図である。FIG. 10 is a diagram illustrating an example of an operation when a failure occurs in a wireless line in the wireless communication system according to the second embodiment. 実施形態２に係る無線通信システムにおいて、無線回線に障害が発生した場合における各無線通信装置の無線フレームの送信タイミングの一例を示す図である。FIG. 6 is a diagram illustrating an example of a transmission timing of a radio frame of each radio communication device when a fault occurs on a radio line in the radio communication system according to the second embodiment. 実施形態２に係る無線通信装置が現用系である場合の動作の一例を示すフロー図である。FIG. 10 is a flowchart illustrating an example of an operation when the wireless communication apparatus according to the second embodiment is an active system. 実施形態２に係る無線通信装置が予備系である場合の動作の一例を示すフロー図である。FIG. 10 is a flowchart illustrating an example of an operation when the wireless communication apparatus according to the second embodiment is a standby system.
　以下、図面を参照して本発明の実施形態について説明する。
（１）実施形態１
　図１に、本実施形態に係る無線通信システムの構成例を示す。図１に示された無線通信システムは、現用系又は予備系となる冗長構成の無線通信装置１０Ａ，１０Ｂと、無線通信装置１０Ａ，１０Ｂと無線回線を介して対向して配置され、現用系又は予備系となる冗長構成の無線通信装置１０Ｃ，１０Ｄと、を含む。以下では、無線通信装置１０Ａ～１０Ｄを特定しない場合には、無線通信装置１０と適宜称す。また、以下では、ある無線通信装置１０から見て、自装置と無線回線を介して対向する無線通信装置１０を、対向側の無線通信装置１０と呼ぶ。無線通信装置１０Ａ～１０Ｄは、対向側の無線通信装置１０との間で無線通信を行う無線通信機能を備える。無線通信装置１０Ａ～１０Ｄは、自装置が現用系である状況では、無線信号の送信及び受信を行う。一方、無線通信装置１０Ａ～１０Ｄは、自装置が予備系である状況では、無線信号の送信を停止し（無線ミュート状態）、無線信号の受信のみを行う。また、無線通信装置１０Ａ～１０Ｄは、自装置が現用系又は予備系のいずれである場合も、同一の周波数を使用して無線信号の送受信を行う。なお、図１においては、現用系の無線通信装置１０（図１では無線通信装置１０Ａ，１０Ｃ）を実線で示し、予備系の無線通信装置１０（図１では無線通信装置１０Ｂ，１０Ｄ）を破線で示している（以降の図２～図４、図６、図８、及び図１１において同じ）。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(1) Embodiment 1
FIG. 1 shows a configuration example of a wireless communication system according to this embodiment. The wireless communication system shown in FIG. 1 is arranged with a redundant configuration of wireless communication devices 10A and 10B serving as a working system or a standby system, and facing the wireless communication devices 10A and 10B via a wireless line. And redundantly configured wireless communication apparatuses 10C and 10D serving as standby systems. Hereinafter, when the wireless communication devices 10A to 10D are not specified, they are appropriately referred to as the wireless communication device 10. In the following description, a wireless communication device 10 that faces the device itself via a wireless line when viewed from a certain wireless communication device 10 is referred to as a wireless communication device 10 on the opposite side. The radio communication devices 10A to 10D have a radio communication function for performing radio communication with the radio communication device 10 on the opposite side. The wireless communication devices 10A to 10D transmit and receive wireless signals in a situation where the own device is an active system. On the other hand, in a situation where the wireless communication devices 10A to 10D are in a standby system, the wireless communication devices 10A to 10D stop transmitting wireless signals (wireless mute state) and only receive wireless signals. The wireless communication devices 10A to 10D transmit and receive wireless signals using the same frequency regardless of whether the wireless communication devices 10A to 10D are active or standby. In FIG. 1, the active wireless communication device 10 ( wireless communication devices 10A and 10C in FIG. 1) is indicated by a solid line, and the standby wireless communication device 10 ( wireless communication devices 10B and 10D in FIG. 1) is indicated by a broken line. (The same applies to FIGS. 2 to 4, FIG. 6, FIG. 8, and FIG. 11).
　図２に、本実施形態に係る無線通信装置１０Ａの構成例を示す。なお、無線通信装置１０Ｂ～１０Ｄの構成も無線通信装置１０Ａの構成と同様である。図２に示された無線通信装置１０Ａは、対向側の無線通信装置１０Ｃ，１０Ｄから無線信号を受信する無線送信部１０１と、対向側の無線通信装置１０Ｃ，１０Ｄへ無線信号を送信する無線受信部１０２と、無線通信装置１０Ａの現用予備の切替を制御する切替制御部１０３と、を備える。切替制御部１０３は、無線通信装置１０Ａが現用系である状況では、対向側の無線通信装置１０Ｃ，１０Ｄのうちの現用系の無線通信装置１０の障害発生状況を検知し、検知した障害発生状況に基づいて、対向側で現用系となる無線通信装置１０を決定する。無線送信部１０１は、対向側で現用系となる無線通信装置１０を示す無線信号を対向側の現用系及び予備系の無線通信装置１０に送信する。この無線信号は、対向側で現用系となる無線通信装置１０を指示する切替指示として対向側に送信されるとする。また、切替制御部１０３は、対向側の現用系の無線通信装置１０から切替指示を受信すると、その切替指示にて指示された無線通信装置１０を確認し、その確認結果に基づいて、無線通信装置１０Ａを現用系又は予備系とする。具体的には、切替制御部１０３は、無線通信装置１０Ａが現用系である状況で、無線通信装置１０Ａが指示された場合、無線通信装置１０Ａを現用系のままとし、無線通信装置１０Ｂが指示された場合、無線通信装置１０Ａを現用系から予備系に切り替える。一方、切替制御部１０３は、無線通信装置１０Ａが予備系である状況で、無線通信装置１０Ａが指示された場合、無線通信装置１０Ａを予備系から現用系に切り替え、無線通信装置１０Ｂが指示された場合、無線通信装置１０Ａを予備系のままとする。 FIG. 2 shows a configuration example of the wireless communication device 10A according to the present embodiment. The configurations of the wireless communication devices 10B to 10D are the same as the configuration of the wireless communication device 10A. The radio communication device 10A illustrated in FIG. 2 includes a radio transmission unit 101 that receives radio signals from the radio communication devices 10C and 10D on the opposite side, and a radio reception that transmits radio signals to the radio communication devices 10C and 10D on the opposite side. Unit 102 and a switching control unit 103 that controls switching of the active backup of the wireless communication device 10A. In a situation where the wireless communication device 10A is the active system, the switching control unit 103 detects a failure occurrence state of the active wireless communication device 10 among the opposing wireless communication devices 10C and 10D, and the detected failure occurrence state Based on the above, the wireless communication device 10 to be the active system is determined on the opposite side. The wireless transmission unit 101 transmits a wireless signal indicating the active wireless communication device 10 on the opposite side to the active and standby wireless communication devices 10 on the opposite side. It is assumed that this wireless signal is transmitted to the opposite side as a switching instruction for instructing the wireless communication device 10 that is the active system on the opposite side. Also, when receiving a switching instruction from the active wireless communication apparatus 10 on the opposite side, the switching control unit 103 confirms the wireless communication apparatus 10 instructed by the switching instruction, and performs wireless communication based on the confirmation result. The apparatus 10A is assumed to be an active system or a standby system. Specifically, when the wireless communication device 10A is instructed in a situation where the wireless communication device 10A is the active system, the switching control unit 103 leaves the wireless communication device 10A as the active system and the wireless communication device 10B instructs If so, the wireless communication device 10A is switched from the active system to the standby system. On the other hand, when the wireless communication device 10A is instructed in a situation where the wireless communication device 10A is the standby system, the switching control unit 103 switches the wireless communication device 10A from the standby system to the active system, and the wireless communication device 10B is instructed. In this case, the wireless communication device 10A remains in the standby system.
　上述したように本実施形態においては、無線通信装置１０Ａ～１０Ｄは、自装置が現用系である状況では、対向側の現用系の無線通信装置１０の障害発生状況に基づいて、対向側で現用系となる無線通信装置１０を指示する切替指示を、対向側の現用系及び予備系の無線通信装置１０に送信する。そして、無線通信装置１０Ａ～１０Ｄは、対向側の現用系の無線通信装置１０から受信した切替指示に基づいて、自装置を現用系又は予備系とする。
　したがって、特許文献１に記載の技術のように、無線通信装置１０Ａ～１０Ｄの外部に専用のコントローラを設けることなく、無線通信装置１０Ａ～１０Ｄの現用予備の切替を行うことができるという効果が得られる。 As described above, in the present embodiment, the wireless communication devices 10A to 10D are active on the opposite side based on the failure occurrence status of the opposite-side active wireless communication device 10 in the situation where the own device is the active system. A switching instruction for instructing the wireless communication device 10 to be the system is transmitted to the active and standby wireless communication devices 10 on the opposite side. Then, the wireless communication devices 10A to 10D set their own device as the active system or the standby system based on the switching instruction received from the active wireless communication device 10 on the opposite side.
Therefore, as in the technique described in Patent Document 1, there is an effect that it is possible to switch the active standby of the radio communication devices 10A to 10D without providing a dedicated controller outside the radio communication devices 10A to 10D. It is done.
（２）実施形態２
（２－１）実施形態２の構成
　本実施形態は、実施形態１の構成及び動作をより具体化したものである。図３に、本実施形態に係る無線通信システムの構成例を示す。図３に示された無線通信システムは、無線通信装置１０Ａ～１０Ｄを有線ネットワークとしての光回線に接続した場合の例である。図３に示された無線通信システムは、図１に示された無線通信システムに対し、無線通信装置１０Ａ，１０Ｂ側に、Ｌ２ＳＷ（Layer 2 switch）２１、光カプラ３１，３２、及びハイブリッド４１を追加し、また、無線通信装置１０Ｃ，１０Ｄ側に、Ｌ２ＳＷ２２、光カプラ３３，３４、及びハイブリッド４２を追加している。Ｌ２ＳＷ２１，２２は、光回線に接続され、光信号の受信及び送信を行う。光カプラ３１～３４は、光信号の分岐及び結合を行う。ハイブリッド４１，４２は、無線信号の分岐及び結合を行う。無線通信装置１０Ａ～１０Ｄは、無線通信機能を備える他、光通信機能を備える。無線通信装置１０Ａ～１０Ｄは、自装置が現用系である場合は、無線信号及び光信号の送信及び受信を行う。一方、無線通信装置１０Ａ～１０Ｄは、自装置が予備系である場合は、無線信号及び光信号の送信を停止し（無線ミュート状態、光ミュート状態）、無線信号及び光信号の受信のみを行う。また、無線通信装置１０Ａ～１０Ｄは、自装置が現用系又は予備系のいずれである場合も、同一の周波数を使用して無線信号の送受信を行う。なお、図３においては、各構成要素間の信号線に関して、通信可能な状態の信号線を実線で示し、ミュート状態の信号線を点線で示している（以降の図４、図６、図８、及び図１１において同じ）。 (2) Embodiment 2
(2-1) Configuration of Embodiment 2 This embodiment is a more specific example of the configuration and operation of Embodiment 1. FIG. 3 shows a configuration example of the wireless communication system according to the present embodiment. The wireless communication system shown in FIG. 3 is an example when the wireless communication devices 10A to 10D are connected to an optical line as a wired network. The wireless communication system shown in FIG. 3 is different from the wireless communication system shown in FIG. 1 in that an L2SW (Layer 2 switch) 21, optical couplers 31 and 32, and a hybrid 41 are provided on the wireless communication devices 10A and 10B side. In addition, an L2SW 22, optical couplers 33 and 34, and a hybrid 42 are added to the wireless communication devices 10C and 10D. The L2SWs 21 and 22 are connected to an optical line, and receive and transmit optical signals. The optical couplers 31 to 34 branch and combine optical signals. The hybrids 41 and 42 branch and combine radio signals. The wireless communication devices 10A to 10D have not only a wireless communication function but also an optical communication function. The wireless communication devices 10A to 10D transmit and receive wireless signals and optical signals when the own device is an active system. On the other hand, when the wireless communication devices 10A to 10D are the standby system, the wireless communication devices 10A to 10D stop transmitting the wireless signal and the optical signal (wireless mute state, optical mute state), and only receive the wireless signal and the optical signal. . The wireless communication devices 10A to 10D transmit and receive wireless signals using the same frequency regardless of whether the wireless communication devices 10A to 10D are active or standby. In FIG. 3, regarding the signal lines between the constituent elements, the signal lines in a communicable state are indicated by solid lines, and the mute state signal lines are indicated by dotted lines (hereinafter, FIG. 4, FIG. 6, FIG. 8). And the same in FIG. 11).
　図４に、本実施形態に係る無線通信装置１０Ａの構成例を示す。なお、無線通信装置１０Ｂ～１０Ｄの構成も無線通信装置１０Ａの構成と同様である。図４に示された無線通信装置１０Ａは、図２に示された無線通信装置１０Ａに対して、光受信部１０４、無線フレーム多重部１０５、無線フレーム抽出部１０６、及び光送信部１０７を追加している。光受信部１０４は、光回線から光カプラ３１を介して光信号を受信する。無線フレーム多重部１０５は、切替制御部１０３の制御の元で、光受信部１０４からの光信号に含まれるデータを無線フレームに載せ替えると共に、対向側で現用系となる無線通信装置１０を指示する切替指示を無線フレームに多重する。本実施形態では、切替指示として、現用系となる無線通信装置１０の装置ＩＤ（IDentifier）を多重するものとする。無線送信部１０１は、無線通信装置１０Ａが現用系である状況では、無線フレーム多重部１０５からの無線フレームを対向側の現用系及び予備系の無線通信装置１０に送信する。なお、無線通信装置１０Ａが予備系である状況では、無線送信部１０１は、切替制御部１０３の制御の元で、無線フレームの送信を停止する。 FIG. 4 shows a configuration example of the wireless communication device 10A according to the present embodiment. The configurations of the wireless communication devices 10B to 10D are the same as the configuration of the wireless communication device 10A. 4 adds an optical receiver 104, a radio frame multiplexer 105, a radio frame extractor 106, and an optical transmitter 107 to the radio communication device 10A shown in FIG. is doing. The optical receiving unit 104 receives an optical signal from the optical line via the optical coupler 31. Under the control of the switching control unit 103, the radio frame multiplexing unit 105 replaces the data included in the optical signal from the optical receiving unit 104 with the radio frame, and instructs the radio communication device 10 to be the active system on the opposite side. The switching instruction to be multiplexed is multiplexed on the radio frame. In the present embodiment, it is assumed that the device ID (IDentifier) of the wireless communication device 10 serving as the active system is multiplexed as the switching instruction. In a situation where the radio communication device 10A is the active system, the radio transmission unit 101 transmits the radio frame from the radio frame multiplexing unit 105 to the active and standby radio communication devices 10 on the opposite side. In a situation where the wireless communication device 10 </ b> A is a standby system, the wireless transmission unit 101 stops transmission of a wireless frame under the control of the switching control unit 103.
　無線受信部１０２は、対向側の現用系の無線通信装置１０から無線フレームを受信する。無線フレーム抽出部１０６は、無線受信部１０２からの無線フレームからデータ及び切替指示を抽出する。光送信部１０７は、無線通信装置１０Ａが現用系である状況では、無線フレーム抽出部１０６からのデータを光信号に載せ替えて光カプラ３２を介して光回線に送信する。なお、無線通信装置１０Ａが予備系である場合、光送信部１０７は、切替制御部１０３の制御の元で、光信号の送信を停止する。 The wireless receiving unit 102 receives a wireless frame from the active wireless communication device 10 on the opposite side. The radio frame extraction unit 106 extracts data and a switching instruction from the radio frame from the radio reception unit 102. In a situation where the wireless communication device 10A is the active system, the optical transmission unit 107 replaces the data from the wireless frame extraction unit 106 with an optical signal and transmits it to the optical line via the optical coupler 32. Note that when the wireless communication device 10 </ b> A is a standby system, the optical transmission unit 107 stops the transmission of the optical signal under the control of the switching control unit 103.
　また、切替制御部１０３は、無線通信装置１０Ａが現用系である状況で、対向側の現用系の無線通信装置１０の無線送信部１０１の障害を検出した場合、無線通信装置１０Ａの無線受信部１０２の障害を検出した場合、及び無線回線の障害を検出した場合、無線フレーム多重部１０５に対し、無線フレームとしてＲＤＩ（Remote Defect Indication）フレームを生成させる。これにより、障害発生のアラームを対向側の現用系及び予備系の無線通信装置１０に通知することができる。なお、以下では、ＲＤＩフレームと区別するために、通常時に送信する無線フレームを通常無線フレームと呼ぶ。また、上記障害の検出は、切替制御部１０３自身で行ってもよく、無線通信装置１０Ａ内に障害検出部（不図示）を設けてその障害検出部が行ってもよい。また、切替制御部１０３は、無線通信装置１０Ａが現用系である状況では、対向側の現用系の無線通信装置１０の障害発生状況に基づいて、対向側で現用系となる無線通信装置１０を決定し、無線フレーム多重部１０５に対し、決定した無線通信装置１０の装置ＩＤを無線フレームに多重させる。例えば、初期状態では、対向側の無線通信装置１０Ｃ，１０Ｄのうちデフォルトで予め設定された方の無線通信装置１０を現用系と決定し、その現用系の無線通信装置１０に障害が発生し、一定時間内に復旧しなければ、その時点で予備系になっている無線通信装置１０を現用系に決定すること等が考えられる。 Further, when the wireless communication device 10A detects the failure of the wireless transmission unit 101 of the active wireless communication device 10 on the opposite side in the situation where the wireless communication device 10A is the active system, the switching control unit 103 performs the wireless reception unit of the wireless communication device 10A. When a failure 102 is detected and when a wireless channel failure is detected, the radio frame multiplexing unit 105 is caused to generate an RDI (Remote Defect Indication) frame as a radio frame. As a result, a failure occurrence alarm can be notified to the active and standby radio communication apparatuses 10 on the opposite side. Hereinafter, in order to distinguish from an RDI frame, a radio frame transmitted at normal time is referred to as a normal radio frame. The failure detection may be performed by the switching control unit 103 itself, or may be performed by a failure detection unit (not shown) provided in the wireless communication device 10A. In addition, in a situation where the wireless communication device 10A is the active system, the switching control unit 103 changes the active wireless communication device 10 on the opposite side based on the failure occurrence state of the active wireless communication device 10 on the opposite side. Then, the wireless frame multiplexing unit 105 multiplexes the determined device ID of the wireless communication device 10 into the wireless frame. For example, in the initial state, the wireless communication device 10 that is preset by default among the opposite-side wireless communication devices 10C and 10D is determined as the active system, and a failure occurs in the active wireless communication device 10. If the wireless communication device 10 is not restored within a certain period of time, the wireless communication device 10 that is a standby system at that time may be determined as the active system.
　また、切替制御部１０３は、対向側の現用系の無線通信装置１０から無線フレームを受信すると、その無線フレームに多重された装置ＩＤを確認し、その確認結果に基づいて、無線通信装置１０Ａを現用系又は予備系とする。具体的には、切替制御部１０３は、無線通信装置１０Ａが現用系である状況で、無線通信装置１０Ａが指示された場合、無線通信装置１０Ａを現用系のままとし、無線通信装置１０Ｂが指示された場合、無線通信装置１０Ａを現用系から予備系に切り替える。一方、切替制御部１０３は、無線通信装置１０Ａが予備系である状況で、無線通信装置１０Ａが指示された場合、無線通信装置１０Ａを予備系から現用系に切り替え、無線通信装置１０Ｂが指示された場合、無線通信装置１０Ａを予備系のままとする。 Further, when receiving the radio frame from the active wireless communication device 10 on the opposite side, the switching control unit 103 confirms the device ID multiplexed in the wireless frame, and determines the wireless communication device 10A based on the confirmation result. The working system or standby system. Specifically, when the wireless communication device 10A is instructed in a situation where the wireless communication device 10A is the active system, the switching control unit 103 leaves the wireless communication device 10A as the active system and the wireless communication device 10B instructs If so, the wireless communication device 10A is switched from the active system to the standby system. On the other hand, when the wireless communication device 10A is instructed in a situation where the wireless communication device 10A is the standby system, the switching control unit 103 switches the wireless communication device 10A from the standby system to the active system, and the wireless communication device 10B is instructed. In this case, the wireless communication device 10A remains in the standby system.
　このように、切替制御部１０３は、対向側の現用系の無線通信装置１０から無線フレームを受信できている間は、その無線フレームに多重された装置ＩＤに基づいて、無線通信装置１０Ａの現用予備を切り替える。しかし、無線回線に障害が発生した場合、対向側の現用系の無線通信装置１０から無線フレームを受信できない。そのため、切替制御部１０３は、無線回線に障害が発生したことを検出した場合は、無線通信装置１０Ａが現用系である状況では、無線通信装置１０Ａを現用系のままとし、無線通信装置１０Ａが予備系である状況では、無線通信装置１０Ａを現用系に切り替える。無線通信装置１０Ｂも同様である。したがって、無線回線に障害が発生した場合には、無線通信装置１０Ａ，１０Ｂが共に現用系となる両系現用状態に遷移する。そして、以降に、無線回線の障害が復旧し、対向側の現用系の無線通信装置１０から無線フレームを受信できるようになると、切替制御部１０３は、その無線フレームに多重された装置ＩＤに基づいて、無線通信装置１０Ａの現用予備を切り替える。これにより、無線通信装置１０Ａ，１０Ｂの一方が予備系になるため、両系現用状態が解消する。 In this way, while the switching control unit 103 is able to receive a radio frame from the active wireless communication device 10 on the opposite side, the switching control unit 103 uses the active wireless communication device 10A based on the device ID multiplexed in the wireless frame. Switch spares. However, when a failure occurs in the wireless line, the wireless frame cannot be received from the active wireless communication device 10 on the opposite side. Therefore, when the switching control unit 103 detects that a failure has occurred in the wireless line, in a situation where the wireless communication device 10A is the active system, the switching control unit 103 leaves the wireless communication device 10A as the active system and the wireless communication device 10A In the situation of the standby system, the radio communication device 10A is switched to the active system. The same applies to the wireless communication device 10B. Therefore, when a failure occurs in the wireless line, the wireless communication devices 10A and 10B transition to the both-system active state where both are active. Thereafter, when the failure of the wireless line is recovered and the wireless frame can be received from the active wireless communication device 10 on the opposite side, the switching control unit 103 is based on the device ID multiplexed in the wireless frame. Thus, the active backup of the wireless communication device 10A is switched. As a result, one of the wireless communication devices 10A and 10B becomes a standby system, and the active state of both systems is eliminated.
（２－２）実施形態２の動作
　以下、本実施形態の動作について説明する。以下では、無線通信装置１０Ａ，１０Ｂ側から無線通信装置１０Ｃ，１０Ｄ側への通信を下り方向、逆の通信を上り方向として説明する。また、以下では、切替制御部１３が障害の発生を検出するものとして説明する。
（２－２－１）無線通信システムの動作
（Ａ）現用系の無線通信装置１０の無線送信部１０１に障害が発生した場合の動作
　図５及び図６に、無線通信装置１０Ａ，１０Ｃが現用系、無線通信装置１０Ｂ，１０Ｄが予備系である状況で、現用系の無線通信装置１０Ａの無線送信部１０１に障害が発生した場合の動作の一例を示す。なお、図５及び図６においては、同じステップには同じ符号を付している。また、図５においては、無線通信装置１０Ａ～１０Ｄは、現用系の状態であれば実線で示し、予備系の状態であれば破線で示している（以降の図７、図９及び図１０において同じ）。また、図６においては、通常無線フレーム及びＲＤＩフレームに付された文字は、それらの無線フレームに多重された装置ＩＤを示している（以降の図８及び図１１において同じ）。また、図５及び図６においては、無線通信装置１０Ａ，１０Ｂ，１０Ｃ，１０Ｄの装置ＩＤはそれぞれＡ，Ｂ，Ｃ，Ｄであるとする（以降の図７～図１２において同じ）。また、以下では、無線通信装置１０Ａ，１０Ｂと無線通信装置１０Ｃ，１０Ｄ間は、Ｌ２ＳＷ２１，２２からのデータがない状態でも、常時、無線フレームを送受信しているものとする。 (2-2) Operation of Embodiment 2 The operation of this embodiment will be described below. Hereinafter, communication from the wireless communication devices 10A and 10B to the wireless communication devices 10C and 10D will be described as a downlink direction, and reverse communication will be described as an uplink direction. In the following description, it is assumed that the switching control unit 13 detects the occurrence of a failure.
(2-2-1) Operation of the Wireless Communication System (A) Operation when a failure occurs in the wireless transmission unit 101 of the active wireless communication device 10 In FIGS. 5 and 6, the wireless communication devices 10A and 10C are in use. An example of an operation when a failure occurs in the wireless transmission unit 101 of the active wireless communication apparatus 10A in a situation where the system and the wireless communication apparatuses 10B and 10D are standby systems will be described. In FIG. 5 and FIG. 6, the same steps are denoted by the same reference numerals. In FIG. 5, the wireless communication devices 10A to 10D are indicated by a solid line in the active system state, and are indicated by a broken line in the standby system state (in FIGS. 7, 9, and 10 below). the same). Further, in FIG. 6, the characters attached to the normal radio frame and the RDI frame indicate the device IDs multiplexed in those radio frames (the same applies to FIGS. 8 and 11 below). 5 and 6, it is assumed that the device IDs of the wireless communication devices 10A, 10B, 10C, and 10D are A, B, C, and D, respectively (the same applies to FIGS. 7 to 12 below). In the following, it is assumed that wireless frames are constantly transmitted and received between the wireless communication devices 10A and 10B and the wireless communication devices 10C and 10D even when there is no data from the L2SWs 21 and 22.
　図５及び図６を参照すると、まず、現在の現用系の無線通信装置１０Ａの無線送信部１０１は、対向側の現在の現用系の無線通信装置１０Ｃの装置ＩＤ「Ｃ」が多重された通常無線フレームを、対向側の無線通信装置１０Ｃ，１０Ｄに送信する（ステップＳ１０１）。しかし、ここでは、無線通信装置１０Ａの無線送信部１０１に障害が発生しており、ステップＳ１０１で無線通信装置１０Ａから送信された通常無線フレームは、無線通信装置１０Ｃ，１０Ｄには到達しない。 Referring to FIGS. 5 and 6, first, the wireless transmission unit 101 of the current working wireless communication device 10 </ b> A is normally configured by multiplexing the device ID “C” of the current working wireless communication device 10 </ b> C on the opposite side. The wireless frame is transmitted to the opposite wireless communication devices 10C and 10D (step S101). However, here, a failure has occurred in the wireless transmission unit 101 of the wireless communication device 10A, and the normal wireless frame transmitted from the wireless communication device 10A in step S101 does not reach the wireless communication devices 10C and 10D.
　無線通信装置１０Ｃ，１０Ｄの各切替制御部１３は、無線通信装置１０Ａから無線フレームを最後に受信してから予め設定された時間を経過し、自装置の無線受信部１０２に障害が発生していないことをもって、対向側の現用系の無線通信装置１０Ａの無線送信部１０１に障害が発生したことを検出する（ステップＳ１０２）。そこで、現用系の無線通信装置１０Ｃの無線送信部１０１は、下り方向での障害発生のアラームを通知するためのＲＤＩフレームを、対向側の無線通信装置１０Ａ，１０Ｂに送信する（ステップＳ１０３）。ここでは、ＲＤＩフレームに多重する装置ＩＤは、対向側の現在の現用系の無線通信装置１０Ａの装置ＩＤ「Ａ」のままとする。無線通信装置１０Ａ，１０Ｂの各切替制御部１３は、対向側の現用系の無線通信装置１０ＣからＲＤＩフレームを受信すると、そのＲＤＩフレームに多重された装置ＩＤを確認する（ステップＳ１０４）。ここでは、現在の現用系の無線通信装置１０Ａの装置ＩＤ「Ａ」が多重されているため、無線通信装置１０Ａ，１０Ｂの各切替制御部１３は、現用予備の切替は行わない。 Each switching control unit 13 of the wireless communication devices 10C and 10D has passed a preset time since the last reception of the wireless frame from the wireless communication device 10A, and a failure has occurred in the wireless reception unit 102 of the own device. If there is no failure, it is detected that a failure has occurred in the wireless transmission unit 101 of the active wireless communication device 10A on the opposite side (step S102). Therefore, the wireless transmission unit 101 of the active wireless communication device 10C transmits an RDI frame for notifying the occurrence of a failure in the downlink direction to the opposite wireless communication devices 10A and 10B (step S103). Here, the device ID multiplexed in the RDI frame is left as the device ID “A” of the current working wireless communication device 10A on the opposite side. When receiving the RDI frame from the opposite-side active wireless communication device 10C, each switching control unit 13 of the wireless communication devices 10A and 10B confirms the device ID multiplexed in the RDI frame (step S104). Here, since the device ID “A” of the current active wireless communication device 10A is multiplexed, each switching control unit 13 of the wireless communication devices 10A and 10B does not switch the active backup.
　一方、無線通信装置１０Ｃの切替制御部１３は、対向側の現用系の無線通信装置１０Ａの無線送信部１０１の障害を検出してから予め設定された一定時間Ｔ１内に障害が復旧したかを判断する。ここでは、一定時間Ｔ１内の復旧がないものとする。そのため、無線通信装置１０Ｃの切替制御部１３は、対向側の現用系を無線通信装置１０Ａから無線通信装置１０Ｂに切り替えると決定する。そして、無線通信装置１０Ｃの切替制御部１３は、ＲＤＩフレームに多重する装置ＩＤを無線通信装置１０Ｂの装置ＩＤ「Ｂ」に変更し（ステップＳ１０５）、無線通信装置１０Ｃの無線送信部１０１は、そのＲＤＩフレームを対向側の無線通信装置１０Ａ，１０Ｂに送信する（ステップＳ１０６）。無線通信装置１０Ａ，１０Ｂの切替制御部１３は、対向側の現用系の無線通信装置１０ＣからＲＤＩフレームを受信すると、そのＲＤＩフレームに多重された装置ＩＤを確認する（ステップＳ１０７）。ここでは、現在の予備系の無線通信装置１０Ｂの装置ＩＤ「Ｂ」が多重されている。そのため、無線通信装置１０Ａの切替制御部１３は、自装置を予備系に切り替え、無線通信装置１０Ｂの切替制御部１３は、自装置を現用系に切り替える（ステップＳ１０８）。 On the other hand, the switching control unit 13 of the wireless communication device 10C detects whether the failure has been recovered within a predetermined time T1 after detecting the failure of the wireless transmission unit 101 of the opposite-side active wireless communication device 10A. to decide. Here, it is assumed that there is no restoration within a certain time T1. Therefore, the switching control unit 13 of the wireless communication device 10C determines to switch the opposite working system from the wireless communication device 10A to the wireless communication device 10B. Then, the switching control unit 13 of the wireless communication device 10C changes the device ID multiplexed in the RDI frame to the device ID “B” of the wireless communication device 10B (step S105), and the wireless transmission unit 101 of the wireless communication device 10C The RDI frame is transmitted to the radio communication apparatuses 10A and 10B on the opposite side (step S106). When receiving the RDI frame from the opposite-side active wireless communication device 10C, the switching control unit 13 of the wireless communication devices 10A and 10B confirms the device ID multiplexed in the RDI frame (step S107). Here, the device ID “B” of the current standby wireless communication device 10B is multiplexed. Therefore, the switching control unit 13 of the wireless communication device 10A switches its own device to the standby system, and the switching control unit 13 of the wireless communication device 10B switches its own device to the working system (step S108).
　上述の通り、現用系の無線通信装置１０Ａの無線送信部１０１に障害が発生した場合に、無線通信装置１０Ａを予備系に切り替え、無線通信装置１０Ｂを現用系に切り替えることができる。 As described above, when a failure occurs in the wireless transmission unit 101 of the active wireless communication device 10A, the wireless communication device 10A can be switched to the standby system, and the wireless communication device 10B can be switched to the active system.
（Ｂ）現用系の無線通信装置１０の無線受信部１０２に障害が発生した場合の動作
　図７及び図８に、無線通信装置１０Ａ，１０Ｃが現用系、無線通信装置１０Ｂ，１０Ｄが予備系である状況で、現用系の無線通信装置１０Ａの無線受信部１０２に障害が発生した場合の動作の一例を示す。
　図７及び図８を参照すると、まず、現在の現用系の無線通信装置１０Ｃの無線送信部１０１は、対向側の現在の現用系の無線通信装置１０Ａの装置ＩＤ「Ａ」が多重された通常無線フレームを、対向側の無線通信装置１０Ａ，１０Ｂに送信する（ステップＳ２０１）。しかし、ここでは、無線通信装置１０Ａの無線受信部１０２に障害が発生しており、ステップＳ２０１で無線通信装置１０Ｃから送信された通常無線フレームは、無線通信装置１０Ａでは受信されない。 (B) Operation when a failure occurs in the wireless reception unit 102 of the active wireless communication apparatus 10 In FIGS. 7 and 8, the wireless communication apparatuses 10A and 10C are the active system, and the wireless communication apparatuses 10B and 10D are the standby system. An example of an operation when a failure occurs in the wireless reception unit 102 of the active wireless communication device 10A in a certain situation will be described.
7 and 8, first, the wireless transmission unit 101 of the current working wireless communication device 10C is normally configured by multiplexing the device ID “A” of the current working wireless communication device 10A on the opposite side. The wireless frame is transmitted to the opposite wireless communication devices 10A and 10B (step S201). However, here, a failure has occurred in the wireless reception unit 102 of the wireless communication device 10A, and the normal wireless frame transmitted from the wireless communication device 10C in step S201 is not received by the wireless communication device 10A.
　無線通信装置１０Ａの無線受信部１０２に障害が発生したことは、無線通信装置１０Ａの切替制御部１３が検出する（ステップＳ２０２）。すると、無線通信装置１０Ａの無線送信部１０１は、上り方向での障害発生のアラームを通知するためのＲＤＩフレームを、対向側の無線通信装置１０Ｃ，１０Ｄに送信する（ステップＳ２０３）。ここでは、ＲＤＩフレームに多重する装置ＩＤは、対向側の現在の現用系の無線通信装置１０Ｃの装置ＩＤ「Ｃ」のままとする。無線通信装置１０Ｃ，１０Ｄの各切替制御部１０３は、対向側の現用系の無線通信装置１０ＡからＲＤＩフレームを受信すると、そのＲＤＩフレームに多重された装置ＩＤを確認する（ステップＳ２０４）。ここでは、現在の現用系の無線通信装置１０Ｃの装置ＩＤ「Ｃ」が多重されているため、無線通信装置１０Ｃ，１０Ｄの各切替制御部１０３は、現用予備の切替は行わない。 The switch control unit 13 of the wireless communication device 10A detects that a failure has occurred in the wireless reception unit 102 of the wireless communication device 10A (step S202). Then, the wireless transmission unit 101 of the wireless communication device 10A transmits an RDI frame for notifying an alarm of occurrence of a failure in the upstream direction to the wireless communication devices 10C and 10D on the opposite side (step S203). Here, the device ID multiplexed in the RDI frame remains the device ID “C” of the current working wireless communication device 10C on the opposite side. When receiving the RDI frame from the opposite-side active wireless communication device 10A, each switching control unit 103 of the wireless communication devices 10C and 10D confirms the device ID multiplexed in the RDI frame (step S204). Here, since the device ID “C” of the current active wireless communication device 10C is multiplexed, each switching control unit 103 of the wireless communication devices 10C and 10D does not switch the active backup.
　また、無線通信装置１０Ｃの切替制御部１０３は、対向側の現用系の無線通信装置１０ＡからＲＤＩフレームを受信してから予め設定された一定時間Ｔ２（Ｔ２＜Ｔ１）内に、障害が復旧したことを示す通常無線フレームを受信したかを判断する。ここでは、一定時間Ｔ２内の復旧がないものとする。そのため、無線通信装置１０Ｃの切替制御部１０３は、対向側の現用系を無線通信装置１０Ａから無線通信装置１０Ｂに切り替えると決定する。そして、無線通信装置１０Ｃの切替制御部１０３は、通常無線フレームに多重する装置ＩＤを無線通信装置１０Ｂの装置ＩＤ「Ｂ」に変更し（ステップＳ２０５）、無線通信装置１０Ｃの無線送信部１０１は、その通常無線フレームを対向側の無線通信装置１０Ａ，１０Ｂに送信する（ステップＳ２０６）。無線通信装置１０Ｂの切替制御部１０３は、対向側の現用系の無線通信装置１０Ｃから通常無線フレームを受信すると、その通常無線フレームに多重された装置ＩＤを確認する（ステップＳ２０７）。ここでは、現在の予備系の無線通信装置１０Ｂの装置ＩＤ「Ｂ」が多重されているため、無線通信装置１０Ｂの切替制御部１０３は、自装置を現用系に切り替える（ステップＳ２０８）。一方、無線通信装置１０Ａの無線受信部１０２には障害が発生しているため、ステップＳ２０６で無線通信装置１０Ｃから送信された通常無線フレームは、無線通信装置１０Ａでは受信されない。そのため、無線通信装置１０Ａの切替制御部１０３は、自装置の無線受信部１０２に障害が発生したことを検出してから予め設定された時間の経過後に、自装置を予備系に切り替える（ステップＳ２０９）。なお、無線通信装置１０Ａが予備系に切り替えるタイミングは任意であり、例えば、無線受信部１０２の障害発生を検出した直後のタイミングであってもよい。 Further, the switching control unit 103 of the wireless communication device 10C has recovered from a failure within a predetermined time T2 (T2 <T1) after receiving the RDI frame from the active wireless communication device 10A on the opposite side. It is determined whether or not a normal radio frame indicating this is received. Here, it is assumed that there is no restoration within a certain time T2. Therefore, the switching control unit 103 of the wireless communication device 10C determines to switch the opposite active system from the wireless communication device 10A to the wireless communication device 10B. Then, the switching control unit 103 of the wireless communication device 10C changes the device ID multiplexed in the normal wireless frame to the device ID “B” of the wireless communication device 10B (step S205), and the wireless transmission unit 101 of the wireless communication device 10C The normal radio frame is transmitted to the opposite radio communication apparatuses 10A and 10B (step S206). When the switching control unit 103 of the wireless communication device 10B receives the normal wireless frame from the active wireless communication device 10C on the opposite side, it checks the device ID multiplexed in the normal wireless frame (step S207). Here, since the device ID “B” of the current standby wireless communication device 10B is multiplexed, the switching control unit 103 of the wireless communication device 10B switches the own device to the active system (step S208). On the other hand, since a failure has occurred in the wireless reception unit 102 of the wireless communication device 10A, the normal wireless frame transmitted from the wireless communication device 10C in step S206 is not received by the wireless communication device 10A. Therefore, the switching control unit 103 of the wireless communication device 10A switches the own device to the standby system after elapse of a preset time after detecting that a failure has occurred in the wireless receiving unit 102 of the own device (step S209). ). Note that the timing at which the radio communication device 10A switches to the standby system is arbitrary, and may be, for example, the timing immediately after the occurrence of a failure in the radio reception unit 102 is detected.
　上述の通り、現用系の無線通信装置１０Ａの無線受信部１０２に障害が発生した場合に、無線通信装置１０Ａを予備系に切り替え、無線通信装置１０Ｂを現用系に切り替えることができる。 As described above, when a failure occurs in the wireless reception unit 102 of the active wireless communication device 10A, the wireless communication device 10A can be switched to the standby system, and the wireless communication device 10B can be switched to the active system.
（Ｃ）無線回線に障害が発生した場合の動作
　無線回線の障害は、例えば、無線通信装置１０のアンテナの前に遮蔽物が置かれた場合等に発生する。図９～図１１に、無線通信装置１０Ａ，１０Ｃが現用系、無線通信装置１０Ｂ，１０Ｄが予備系である状況で、無線回線に障害が発生した場合の動作の一例を示す。なお、図９及び図１０は、図９の処理に続いて図１０の処理が行われることを示しており、図９及び図１０のステップＳ３１５は同じステップを指している。 (C) Operation when a failure occurs in a wireless line A failure in a wireless line occurs, for example, when a shield is placed in front of the antenna of the wireless communication device 10. FIG. 9 to FIG. 11 show an example of the operation when a failure occurs in the radio line in a situation where the radio communication devices 10A and 10C are the active system and the radio communication devices 10B and 10D are the standby system. 9 and 10 show that the process of FIG. 10 is performed subsequent to the process of FIG. 9, and step S315 in FIGS. 9 and 10 indicates the same step.
　図９～図１１を参照すると、まず、現在の現用系の無線通信装置１０Ａの無線送信部１０１は、対向側の現在の現用系の無線通信装置１０Ｃの装置ＩＤ「Ｃ」が多重された通常無線フレームを、対向側の無線通信装置１０Ｃ，１０Ｄに送信する（ステップＳ３０１）。また、現在の現用系の無線通信装置１０Ｃの無線送信部１０１は、対向側の現在の現用系の無線通信装置１０Ａの装置ＩＤ「Ａ」が多重された通常無線フレームを、対向側の無線通信装置１０Ａ，１０Ｂに送信する（ステップＳ３０２）。しかし、ここでは、無線回線の障害が発生しており、ステップＳ３０１で無線通信装置１０Ａから送信された通常無線フレームは、無線通信装置１０Ｃ，１０Ｄに到達しない。また、ステップＳ３０２で無線通信装置１０Ｃから送信された通常無線フレームは、無線通信装置１０Ａ，１０Ｂに到達しない。 Referring to FIGS. 9 to 11, first, the wireless transmission unit 101 of the current working wireless communication device 10A is a normal one in which the device ID “C” of the current working wireless communication device 10C on the opposite side is multiplexed. The wireless frame is transmitted to the opposite wireless communication devices 10C and 10D (step S301). In addition, the wireless transmission unit 101 of the current working wireless communication device 10C transmits the normal wireless frame in which the device ID “A” of the current working wireless communication device 10A on the opposite side is multiplexed to the wireless communication on the opposite side. It transmits to apparatus 10A, 10B (step S302). However, here, a failure of the wireless line has occurred, and the normal wireless frame transmitted from the wireless communication device 10A in step S301 does not reach the wireless communication devices 10C and 10D. Further, the normal radio frame transmitted from the radio communication device 10C in step S302 does not reach the radio communication devices 10A and 10B.
　無線回線の障害は、無線通信装置１０Ａ～１０Ｄの各切替制御部１０３が検出する（ステップＳ３０３，Ｓ３０４）。すると、無線通信装置１０Ａ～１０Ｄの各切替制御部１０３は、無線回線の障害を検出してから予め設定された一定時間Ｔ３（Ｔ２＜Ｔ１＜Ｔ３）内に障害が復旧したかを判断する（ステップＳ３０５，Ｓ３０６）。ここでは、一定時間Ｔ３内の復旧がないものとする。そのため、無線通信装置１０Ｂ，１０Ｄの各切替制御部１０３は、自装置を現用系に切り替える（ステップＳ３０７，Ｓ３０８）。これにより、無線通信装置１０Ａ，１０Ｂが共に現用系となり、また、無線通信装置１０Ｃ，１０Ｄが共に現用系となる両系現用状態に遷移する。そのため、無線通信装置１０Ａ，１０Ｂの各無線送信部１０１が、対向側の無線通信装置１０Ｃ，１０ＤにＲＤＩフレームを送信する（ステップＳ３０９，Ｓ３１０）。このＲＤＩフレームに多重する装置ＩＤは、予め設定しておくことが可能であり、ここでは、対向側で障害発生前に現用系であった無線通信装置１０Ｃの装置ＩＤ「Ｃ」を多重するものとする。また、無線通信装置１０Ｃ，１０Ｄの各無線送信部１０１が、対向側の無線通信装置１０Ａ，１０ＢにＲＤＩフレームを送信する（ステップＳ３１１，Ｓ３１２）。このＲＤＩフレームに多重する装置ＩＤは、予め設定しておくことが可能であり、ここでは、対向側で障害発生前に現用系であった無線通信装置１０Ａの装置ＩＤ「Ａ」を多重するものとする。 The failure of the wireless line is detected by each switching control unit 103 of the wireless communication devices 10A to 10D (steps S303 and S304). Then, each switching control unit 103 of the wireless communication devices 10A to 10D determines whether or not the failure has been recovered within a predetermined time T3 (T2 <T1 <T3) after detecting the failure of the wireless line (T2 <T1 <T3). Steps S305 and S306). Here, it is assumed that there is no restoration within a certain time T3. Therefore, each switching control unit 103 of the wireless communication devices 10B and 10D switches its own device to the active system (steps S307 and S308). As a result, the wireless communication devices 10A and 10B are both active, and the wireless communication devices 10C and 10D are both active. Therefore, each wireless transmission unit 101 of the wireless communication devices 10A and 10B transmits an RDI frame to the opposite wireless communication devices 10C and 10D (steps S309 and S310). The device ID multiplexed in the RDI frame can be set in advance. Here, the device ID “C” of the wireless communication device 10C that was the active system before the failure occurred on the opposite side is multiplexed here. And In addition, each of the wireless transmission units 101 of the wireless communication devices 10C and 10D transmits an RDI frame to the opposite wireless communication devices 10A and 10B (steps S311 and S312). The device ID multiplexed in the RDI frame can be set in advance, and here, the device ID “A” of the wireless communication device 10A that was the active system before the failure occurred on the opposite side is multiplexed here. And
　このように、無線回線に障害が発生した場合、例えば、下り方向の通信においては、無線通信装置１０Ａ，１０Ｂが共にＲＤＩフレームを送信することになるが、無線回線の障害発生中は、このＲＤＩフレームは対向側の無線通信装置１０Ｃ，１０Ｄには到達しない。そのため、ＲＤＩフレームが対向側の無線通信装置１０Ｃ，１０Ｄに到達するのは、無線回線の障害が復旧した後になる。しかし、無線回線の障害が復旧したとしても、無線通信装置１０Ａ，１０ＢがＲＤＩフレームを送信する送信タイミングが同じであれば、ＲＤＩフレーム同士が衝突してしまう。その結果、どちらのＲＤＩフレームも対向側の無線通信装置１０Ｃ，１０Ｄには到着しないことになる。そうすると、無線回線の障害が復旧したものの、無線通信装置１０Ｃ，１０Ｄは、ＲＤＩフレームを受信できず、どちらが現用系のままでいるか判断ができないため、両系現用状態を継続したままとなってしまう。また、無線回線の障害が復旧した時点でＲＤＩフレームを通常無線フレームに切り替える実装とした場合も、通常無線フレーム同士が衝突してしまう可能性がある。同様の問題が上り方向の通信でも生じ得る。 As described above, when a failure occurs in the wireless line, for example, in downlink communication, the wireless communication devices 10A and 10B both transmit RDI frames. The frame does not reach the radio communication devices 10C and 10D on the opposite side. Therefore, the RDI frame arrives at the opposite radio communication apparatuses 10C and 10D only after the failure of the radio line is recovered. However, even if the failure of the wireless line is recovered, the RDI frames collide if the transmission timings at which the wireless communication devices 10A and 10B transmit the RDI frame are the same. As a result, neither RDI frame arrives at the opposite radio communication apparatuses 10C and 10D. Then, although the failure of the wireless line has been recovered, the wireless communication devices 10C and 10D cannot receive the RDI frame and cannot determine which is the active system, so that both systems remain in the active state. . Further, even when the RDI frame is switched to the normal radio frame when the failure of the radio line is recovered, the normal radio frames may collide with each other. Similar problems can occur in upstream communications.
　そこで本実施形態においては、無線回線に障害が発生した場合、現用系決定シーケンスを実行する。現用系決定シーケンスにおいては、現用系になった無線通信装置１０Ａ，１０Ｂにおける無線フレームの送信タイミングが、無線通信装置１０Ａ，１０Ｂが交互に無線フレームを送信するよう予め決められている。また、現用系になった無線通信装置１０Ｃ，１０Ｄにおける無線フレームの送信タイミングが、無線通信装置１０Ｃ，１０Ｄが交互に無線フレームを送信するよう予め決められている。図１２に、無線フレームの送信タイミングの一例を示す。なお、図１２において、時間軸上の文字は、その時点で送信を行っている無線通信装置１０の装置ＩＤを示している。図１２を参照すると、例えば、無線通信装置１０Ａ，１０Ｂの場合、無線回線の障害発生時に現用系であった無線通信装置１０Ａは、障害発生以降も予め設定された時間の間は、現用系として無線フレームを送信し続ける。ただし、無線フレームは、障害発生前は通常無線フレーム、障害発生以降はＲＤＩフレームを送信する。そして、障害の発生から予め設定された一定時間Ｔ３内に無線回線の障害が復旧しないと、無線通信装置１０Ｂも現用系となる。そのため、無線通信装置１０Ａ，１０Ｂが共にＲＤＩフレームを送信する。ただし、無線通信装置１０Ａ，１０Ｂの無線フレームの送信タイミングは予め決められているため、無線通信装置１０Ａ，１０Ｂは、交互にＲＤＩフレームを送信する。そして、以降に無線回線の障害が復旧した場合、その時点で送信されているのは無線通信装置１０ＡのＲＤＩフレームであるため、そのＲＤＩフレームが対向側の無線通信装置１０Ｃ，１０Ｄに受信され、そのＲＤＩフレームに多重された装置ＩＤ「Ｃ」の無線通信装置１０Ｃが現用系を継続し、他方の無線通信装置１０Ｄが予備系に切り替わる。このように無線通信装置１０Ａ，１０Ｂの送信タイミングを予め決めておくことで、障害復旧後に、無線通信装置１０Ａ，１０ＢからのＲＤＩフレーム（又は通常無線フレーム）同志が衝突することが回避される。なお、無線通信装置１０Ｃ，１０Ｄにおける無線フレームの送信タイミングも同様である。 Therefore, in the present embodiment, when a failure occurs in the wireless line, an active system determination sequence is executed. In the working system determination sequence, the wireless frame transmission timings in the wireless communication apparatuses 10A and 10B that are in the working system are determined in advance so that the wireless communication apparatuses 10A and 10B alternately transmit the wireless frames. In addition, the transmission timing of the radio frame in the radio communication devices 10C and 10D that are in the active system is determined in advance so that the radio communication devices 10C and 10D transmit radio frames alternately. FIG. 12 shows an example of radio frame transmission timing. In FIG. 12, the characters on the time axis indicate the device ID of the wireless communication device 10 that is transmitting at that time. Referring to FIG. 12, for example, in the case of wireless communication devices 10A and 10B, the wireless communication device 10A that was the active system at the time of occurrence of the failure of the wireless line is set as the active system for a preset time after the occurrence of the failure. Continue to transmit radio frames. However, the radio frame transmits a normal radio frame before the occurrence of a failure and an RDI frame after the occurrence of the failure. If the failure of the wireless line is not recovered within a predetermined time T3 set in advance from the occurrence of the failure, the wireless communication device 10B also becomes the active system. Therefore, the radio communication devices 10A and 10B both transmit RDI frames. However, since the radio frame transmission timings of the radio communication devices 10A and 10B are determined in advance, the radio communication devices 10A and 10B alternately transmit RDI frames. Then, when the failure of the wireless line is recovered thereafter, since the RDI frame of the wireless communication device 10A is transmitted at that time, the RDI frame is received by the opposite wireless communication devices 10C and 10D, The wireless communication device 10C with the device ID “C” multiplexed in the RDI frame continues the active system, and the other wireless communication device 10D switches to the standby system. Thus, by determining the transmission timings of the radio communication devices 10A and 10B in advance, it is possible to avoid collision between RDI frames (or normal radio frames) from the radio communication devices 10A and 10B after the failure recovery. The radio frame transmission timing in the radio communication devices 10C and 10D is the same.
　再度図９～図１１を参照すると、無線通信装置１０Ａ，１０Ｂの各無線送信部１０１は、ステップＳ３０９，Ｓ３１０において、交互にＲＤＩフレームを送信する。そのため、無線回線の障害復旧後に、無線通信装置１０Ａ，１０Ｂが送信するＲＤＩフレーム同士が衝突することが回避され、復旧直後に送信されているＲＤＩフレームが対向側の無線通信装置１０Ｃ，１０Ｄに最初に受信される。同様に、無線通信装置１０Ｃ，１０Ｄの各無線送信部１０１は、ステップＳ３１１，Ｓ３１２において、交互にＲＤＩフレームを送信する。そのため、無線回線の障害復旧後に、無線通信装置１０Ｃ，１０Ｄが送信するＲＤＩフレーム同士が衝突することが回避され、復旧直後に送信されているＲＤＩフレームが対向側の無線通信装置１０Ａ，１０Ｂに最初に受信される。ここでは、無線回線の障害復旧後、最も早く対向側に到達したのが、無線通信装置１０Ａが送信したＲＤＩフレームであったとする（ステップＳ３１３）。この場合、無線通信装置１０Ｃ，１０Ｄの各切替制御部１０３は、対向側の無線通信装置１０ＡからＲＤＩフレームを受信すると、そのＲＤＩフレームに多重された装置ＩＤを確認する（ステップＳ３１４）。ここでは、無線通信装置１０Ｃの装置ＩＤ「Ｃ」が多重されているため、無線通信装置１０Ｄの切替制御部１０３が自装置を予備系に切り替える（ステップＳ３１５）。これにより、無線通信装置１０Ｃ，１０Ｄ側の両系現用状態は解消する。そのため、以降は、無線通信装置１０Ｃのみが、ＲＤＩフレームから切り替えた通常無線フレームを、無線通信装置１０Ａ，１０Ｂに送信する（ステップＳ３１６）。無線通信装置１０Ａ，１０Ｂの各切替制御部１０３は、対向側の無線通信装置１０Ｃから通常無線フレームを受信すると、その通常無線フレームに多重された装置ＩＤを確認する（ステップＳ３１７）。ここでは、無線通信装置１０Ａの装置ＩＤ「Ａ」が多重されているため、無線通信装置１０Ｂの切替制御部１０３が自装置を予備系に切り替える（ステップＳ３１８）。これにより、無線通信装置１０Ａ，１０Ｂ側でも両系現用状態は解消する。 Referring to FIGS. 9 to 11 again, the wireless transmission units 101 of the wireless communication devices 10A and 10B alternately transmit RDI frames in steps S309 and S310. For this reason, it is avoided that the RDI frames transmitted by the wireless communication devices 10A and 10B collide after the failure of the wireless line is restored, and the RDI frame transmitted immediately after the recovery is first sent to the opposite wireless communication devices 10C and 10D. Received. Similarly, the wireless transmission units 101 of the wireless communication devices 10C and 10D alternately transmit RDI frames in steps S311 and S312. For this reason, it is avoided that the RDI frames transmitted by the wireless communication devices 10C and 10D collide after the failure of the wireless line is recovered, and the RDI frame transmitted immediately after the recovery is first sent to the opposite wireless communication devices 10A and 10B. Received. Here, it is assumed that the RDI frame transmitted by the wireless communication device 10A arrives at the opposite side earliest after the failure of the wireless line is recovered (step S313). In this case, when receiving the RDI frame from the opposite-side wireless communication device 10A, each switching control unit 103 of the wireless communication devices 10C and 10D confirms the device ID multiplexed in the RDI frame (step S314). Here, since the device ID “C” of the wireless communication device 10C is multiplexed, the switching control unit 103 of the wireless communication device 10D switches the own device to the standby system (step S315). As a result, the active state of both systems on the wireless communication devices 10C and 10D side is canceled. Therefore, thereafter, only the radio communication device 10C transmits the normal radio frame switched from the RDI frame to the radio communication devices 10A and 10B (step S316). When receiving the normal wireless frame from the opposite-side wireless communication device 10C, each switching control unit 103 of the wireless communication devices 10A and 10B confirms the device ID multiplexed in the normal wireless frame (step S317). Here, since the device ID “A” of the wireless communication device 10A is multiplexed, the switching control unit 103 of the wireless communication device 10B switches the own device to the standby system (step S318). As a result, the active status of both systems is canceled on the wireless communication devices 10A and 10B side.
　上述の通り、無線回線に障害が発生した場合、無線通信装置１０Ａ，１０Ｂ側及び無線通信装置１０Ｃ，１０Ｄ側は共に両系現用状態に遷移するが、障害復旧後の無線フレーム同士の衝突が回避されるため、対向側で無線フレームを受信でき、両系現用状態を解消することができる。 As described above, when a failure occurs in the wireless line, both the wireless communication devices 10A and 10B and the wireless communication devices 10C and 10D transition to the active state of both systems, but avoid collision between wireless frames after failure recovery. Therefore, the radio frame can be received on the opposite side, and the active status of both systems can be eliminated.
（２－２－２）無線通信装置１０Ａ～１０Ｄの動作
（Ａ）現用系である場合の動作
　図１３に、無線通信装置１０が現用系である場合の動作の一例を示す。図１３を参照すると、まず、切替制御部１０３は、無線障害の発生が検出されたか判断する（ステップＳ４０１）。無線障害とは、対向側の現用系の無線通信装置１０の無線送信部１０１の障害、自装置の無線受信部１０２の障害、及び無線回線の障害を指す（以降の図１４において同じ）。ステップＳ４０１において、無線障害が検出された場合（ステップＳ４０１のＹｅｓ）、無線送信部１０１は、対向側の現用系及び予備系の無線通信装置１０にＲＤＩフレームを送信する（ステップＳ４０２）。このＲＤＩフレームには対向側で障害発生前に現用系であった無線通信装置１０の装置ＩＤを多重する。続いて、切替制御部１０３は、無線障害の発生を検出してから予め設定された一定時間Ｔ１内に無線障害が復旧したかを判断する（ステップＳ４０３）。ステップＳ４０３において、一定時間Ｔ１内に無線障害が復旧した場合（ステップＳ４０３のＮｏ）、切替制御部１０３は、自装置を現用系のままとする（ステップＳ４０８）。一方、ステップＳ４０３において、一定時間Ｔ１内に無線障害が復旧しない場合（ステップＳ４０３のＹｅｓ）、切替制御部１０３は、ＲＤＩフレームに多重する装置ＩＤを、対向側で障害発生前に予備系であった無線通信装置１０の装置ＩＤに変更し、無線送信部１０１は、そのＲＤＩフレームを対向側の現用系及び予備系の無線通信装置１０に送信する（ステップＳ４０４）。続いて、切替制御部１０３は、無線障害の発生を検出してから予め設定された一定時間Ｔ３（Ｔ１＜Ｔ３）内に無線障害が復旧したかを判断する（ステップＳ４０５）。ステップＳ４０５において、一定時間Ｔ３内に無線障害が復旧した場合（ステップＳ４０５のＮｏ）、無線送信部１０１は、対向側の現用系及び予備系の無線通信装置１０に通常無線フレームを送信する。このとき、対向側では、ステップＳ４０４で送信されたＲＤＩフレームが受信できていれば、現用系の無線通信装置１０の切替が行われていることになる（ステップＳ４０７）。一方、ステップＳ４０５において、一定時間Ｔ３内に無線障害が復旧しない場合（ステップＳ４０５のＹｅｓ）、上述した現用系決定シーケンスが行われる（ステップＳ４０６）。 (2-2-2) Operations of Radio Communication Devices 10A to 10D (A) Operation when Active System is Used FIG. 13 shows an example of operation when the radio communication device 10 is an active system. Referring to FIG. 13, first, the switching control unit 103 determines whether the occurrence of a radio failure is detected (step S401). The wireless failure refers to a failure of the wireless transmission unit 101 of the active wireless communication device 10 on the opposite side, a failure of the wireless reception unit 102 of the own device, and a failure of the wireless line (the same applies to FIG. 14 below). If a wireless failure is detected in step S401 (Yes in step S401), the wireless transmission unit 101 transmits an RDI frame to the opposite-side active and standby wireless communication devices 10 (step S402). In this RDI frame, the device ID of the wireless communication device 10 that was the active system before the occurrence of a failure on the opposite side is multiplexed. Subsequently, the switching control unit 103 determines whether the wireless failure has been recovered within a predetermined time T1 after detecting the occurrence of the wireless failure (step S403). In step S403, when the wireless failure is recovered within the predetermined time T1 (No in step S403), the switching control unit 103 keeps its own device as the active system (step S408). On the other hand, if the wireless failure is not recovered within the predetermined time T1 in step S403 (Yes in step S403), the switching control unit 103 sets the device ID multiplexed in the RDI frame as a standby system before the failure occurs on the opposite side. The wireless transmission unit 101 transmits the RDI frame to the active and standby wireless communication devices 10 on the opposite side (step S404). Subsequently, the switching control unit 103 determines whether or not the wireless failure has been recovered within a preset time T3 (T1 <T3) after detecting the occurrence of the wireless failure (step S405). In step S405, when the wireless failure is recovered within a predetermined time T3 (No in step S405), the wireless transmission unit 101 transmits a normal wireless frame to the active and standby wireless communication apparatuses 10 on the opposite side. At this time, if the RDI frame transmitted in step S404 can be received on the opposite side, the active wireless communication device 10 has been switched (step S407). On the other hand, if the wireless failure is not recovered within the predetermined time T3 in step S405 (Yes in step S405), the above-described active system determination sequence is performed (step S406).
　また、ステップＳ４０１において、無線障害の発生が検出されない場合（ステップＳ４０１のＮｏ）、切替制御部１０３は、対向側の現用系の無線通信装置１０からＲＤＩフレームが受信されたか判断する（ステップＳ４０９）。ステップＳ４０９において、ＲＤＩフレームが受信された場合（ステップＳ４０９のＹｅｓ）、切替制御部１０３は、受信されたＲＤＩフレームに多重された装置ＩＤが自装置の装置ＩＤと一致するかを判断する（ステップＳ４１０）。ステップＳ４１０において、装置ＩＤが一致しない場合（ステップＳ４１０のＮｏ）、切替制御部１０３は、自装置を予備系に切り替える（ステップＳ４１５）。一方、ステップＳ４１０において、装置ＩＤが一致した場合（ステップＳ４１０のＹｅｓ）、切替制御部１０３は、ステップＳ４０９でのＲＤＩフレームの受信により無線障害を検出してから予め設定された一定時間Ｔ２（Ｔ２＜Ｔ１＜Ｔ３）内に無線障害が復旧したかを判断する（ステップＳ４１１）。ステップＳ４１１において、一定時間Ｔ２内に無線障害が復旧した場合（ステップＳ４１１のＮｏ）、切替制御部１０３は、自装置を現用系のままとする（ステップＳ４１４）。一方、ステップＳ４１１において、一定時間Ｔ２内に無線障害が復旧しない場合（ステップＳ４１１のＹｅｓ）、切替制御部１０３は、通常無線フレームに多重する装置ＩＤを、対向側で障害発生前に予備系であった無線通信装置１０の装置ＩＤに変更し、無線送信部１０１は、その通常無線フレームを対向側の現用系及び予備系の無線通信装置１０に送信する（ステップＳ４１２）。対向側では、ステップＳ４１２で送信された通常無線フレームが受信できれば、現用系の無線通信装置１０の切替が行われる（ステップＳ４１３）。 If no occurrence of a radio failure is detected in step S401 (No in step S401), the switching control unit 103 determines whether an RDI frame is received from the opposite-side active radio communication device 10 (step S409). . If an RDI frame is received in step S409 (Yes in step S409), the switching control unit 103 determines whether the device ID multiplexed in the received RDI frame matches the device ID of the own device (step S409). S410). If the device IDs do not match in step S410 (No in step S410), the switching control unit 103 switches the own device to the standby system (step S415). On the other hand, if the device IDs match in step S410 (Yes in step S410), the switching control unit 103 detects a radio failure by receiving the RDI frame in step S409, and then sets a predetermined time T2 (T2). It is determined whether the wireless failure has been recovered within <T1 <T3) (step S411). In step S411, when the wireless failure is recovered within the predetermined time T2 (No in step S411), the switching control unit 103 keeps its own device as the active system (step S414). On the other hand, if the wireless failure is not recovered within the predetermined time T2 in step S411 (Yes in step S411), the switching control unit 103 sets the device ID multiplexed in the normal wireless frame in the standby system before the failure occurs on the opposite side. The wireless transmission unit 101 transmits the normal wireless frame to the active and standby wireless communication devices 10 on the opposite side (step S412). On the opposite side, if the normal radio frame transmitted in step S412 can be received, the active radio communication device 10 is switched (step S413).
　また、ステップＳ４０９において、ＲＤＩフレームが受信されない場合（ステップＳ４０９のＮｏ）、切替制御部１０３は、対向側の現用系の無線通信装置１０から受信された通常無線フレームに多重された装置ＩＤが自装置の装置ＩＤと一致するかを判断する（ステップＳ４１６）。ステップＳ４１６において、装置ＩＤが一致しない場合（ステップＳ４１６のＮｏ）、切替制御部１０３は、自装置を予備系に切り替える（ステップＳ４１８）。一方、ステップＳ４１６において、装置ＩＤが一致した場合（ステップＳ４１６のＹｅｓ）、切替制御部１０３は、自装置を現用系のままとする（ステップＳ４１７）。
　なお、ステップＳ４０４においては、ＲＤＩフレームに多重する装置ＩＤを変更していた。しかし、無線障害が無線回線の障害である場合は、ステップＳ４０２、Ｓ４０４のＲＤＩフレームが対向側で受信されないため、装置ＩＤを変更せず、そのままとしてよい。 If the RDI frame is not received in step S409 (No in step S409), the switching control unit 103 determines that the device ID multiplexed in the normal radio frame received from the opposite-side active radio communication device 10 is the own. It is determined whether the device ID matches the device ID (step S416). If the device IDs do not match in step S416 (No in step S416), the switching control unit 103 switches the own device to the standby system (step S418). On the other hand, when the device IDs match in step S416 (Yes in step S416), the switching control unit 103 keeps the own device as the active system (step S417).
In step S404, the device ID multiplexed in the RDI frame has been changed. However, if the wireless failure is a failure in the wireless line, the RDI frame in steps S402 and S404 is not received on the opposite side, and the device ID may be left unchanged.
（Ｂ）予備系である場合の動作
　図１４に、無線通信装置１０が予備系である場合の動作の一例を示す。図１４を参照すると、まず、切替制御部１０３は、無線障害の発生が検出されたか判断する（ステップＳ５０１）。ステップＳ５０１において、無線障害の発生が検出された場合（ステップＳ５０１のＹｅｓ）、切替制御部１０３は、無線障害を検出してから予め設定された一定時間Ｔ３内に無線障害が復旧したかを判断する（ステップＳ５０２）。ステップＳ５０２において、一定時間Ｔ３内に無線障害が復旧した場合（ステップＳ５０２のＮｏ）、切替制御部１０３は、自装置を予備系のままとする（ステップＳ５０４）。一方、ステップＳ５０２において、一定時間Ｔ３内に無線障害が復旧しない場合（ステップＳ５０２のＹｅｓ）、上述した現用系決定シーケンスが行われる（ステップＳ５０３）。 (B) Operation in case of standby system FIG. 14 shows an example of the operation in the case where the wireless communication apparatus 10 is a standby system. Referring to FIG. 14, first, the switching control unit 103 determines whether the occurrence of a radio failure is detected (step S501). When the occurrence of a radio failure is detected in step S501 (Yes in step S501), the switching control unit 103 determines whether the radio failure has been recovered within a predetermined time T3 after detecting the radio failure. (Step S502). In step S502, when the wireless failure is recovered within the predetermined time T3 (No in step S502), the switching control unit 103 keeps its own device as a standby system (step S504). On the other hand, in step S502, when the wireless failure is not recovered within a certain time T3 (Yes in step S502), the above-described active system determination sequence is performed (step S503).
　また、ステップＳ５０１において、無線障害の発生が検出されない場合（ステップＳ５０１のＮｏ）、切替制御部１０３は、対向側の現用系の無線通信装置１０からＲＤＩフレームが受信されたか判断する（ステップＳ５０５）。ステップＳ５０５において、ＲＤＩフレームが受信された場合（ステップＳ５０５のＹｅｓ）、切替制御部１０３は、受信されたＲＤＩフレームに多重された装置ＩＤが自装置の装置ＩＤと一致するかを判断する（ステップＳ５０６）。ステップＳ５０６において、装置ＩＤが一致しない場合（ステップＳ５０６のＮｏ）、切替制御部１０３は、自装置を予備系のままとする（ステップＳ５０８）。一方、ステップＳ５０６において、装置ＩＤが一致した場合（ステップＳ５０６のＹｅｓ）、自装置を現用系に切り替える（ステップＳ５０７）。 If no occurrence of a wireless failure is detected in step S501 (No in step S501), the switching control unit 103 determines whether an RDI frame has been received from the opposite-side active wireless communication device 10 (step S505). . When an RDI frame is received in step S505 (Yes in step S505), the switching control unit 103 determines whether the device ID multiplexed in the received RDI frame matches the device ID of the own device (step S505). S506). If the device IDs do not match in step S506 (No in step S506), the switching control unit 103 leaves the own device as a standby system (step S508). On the other hand, if the device IDs match in step S506 (Yes in step S506), the own device is switched to the active system (step S507).
　また、ステップＳ５０５において、ＲＤＩフレームが受信されない場合（ステップＳ５０５のＮｏ）、切替制御部１０３は、対向側の現用系の無線通信装置１０から受信された通常無線フレームに多重された装置ＩＤが自装置の装置ＩＤと一致するかを判断する（ステップＳ５０９）。ステップＳ５０９において、装置ＩＤが一致しない場合（ステップＳ５０９のＮｏ）、切替制御部１０３は、自装置を予備系のままとする（ステップＳ５１１）。一方、ステップＳ５０９において、装置ＩＤが一致した場合（ステップＳ５０９のＹｅｓ）、切替制御部１０３は、自装置を現用系に切り替える（ステップＳ５１０）。 If the RDI frame is not received in step S505 (No in step S505), the switching control unit 103 determines that the device ID multiplexed in the normal radio frame received from the opposite-side active radio communication device 10 is the own. It is determined whether the device ID matches the device ID (step S509). If the device IDs do not match in step S509 (No in step S509), the switching control unit 103 leaves the own device as a standby system (step S511). On the other hand, if the device IDs match in step S509 (Yes in step S509), the switching control unit 103 switches the own device to the active system (step S510).
（２－３）実施形態２の効果
　上述したように本実施形態においては、無線通信装置１０Ａ～１０Ｄは、自装置が現用系である状況では、対向側の現用系の無線通信装置１０の障害発生状況に基づいて、対向側で現用系となる無線通信装置１０の装置ＩＤを多重した無線フレームを、対向側の現用系及び予備系の無線通信装置１０に送信する。そして、無線通信装置１０Ａ～１０Ｄは、対向側の現用系の無線通信装置１０から受信した無線フレームに多重された装置ＩＤに基づいて、自装置を現用系又は予備系とする。したがって、特許文献１に記載の技術のように、無線通信装置１０Ａ～１０Ｄの外部に専用のコントローラを設けることなく、無線通信装置１０Ａ～１０Ｄの現用予備の切替を行うことができるという効果が得られる。また、専用のコントローラが不要になるため、システム構成を簡易化でき、システム全体のコストを低減することができる。また、専用のコントローラが不要になるため、コントローラのある外部装置の近くに無線通信装置１０を配置する必要がなくなるため、実装面の制約も少なくなる。 (2-3) Effect of Embodiment 2 As described above, in the present embodiment, the radio communication devices 10A to 10D have a failure of the active radio communication device 10 on the opposite side in a situation where the own device is the active system. Based on the state of occurrence, a radio frame in which the device ID of the wireless communication device 10 that is the active system on the opposite side is multiplexed is transmitted to the active and standby wireless communication devices 10 on the opposite side. Then, the radio communication devices 10A to 10D set their own device as the active or standby system based on the device ID multiplexed in the radio frame received from the opposite-side active radio communication device 10. Therefore, as in the technique described in Patent Document 1, there is an effect that it is possible to switch the active standby of the radio communication devices 10A to 10D without providing a dedicated controller outside the radio communication devices 10A to 10D. It is done. In addition, since a dedicated controller is not required, the system configuration can be simplified and the cost of the entire system can be reduced. In addition, since a dedicated controller is not required, it is not necessary to place the wireless communication device 10 near an external device having the controller, so that restrictions on the mounting surface are reduced.
　また、本実施形態においては、無線回線に障害が発生し、両系現用状態に遷移した場合における、無線通信装置１０Ａ，１０Ｂの無線フレームの送信タイミングが、無線通信装置１０Ａ，１０Ｂが交互に無線フレームを送信するよう予め決められている。同様に、無線通信装置１０Ｃ，１０Ｄの無線フレームの送信タイミングが、無線通信装置１０Ｃ，１０Ｄが交互に無線フレームを送信するよう予め決められている。したがって、無線回線の障害復旧後に、無線通信装置１０Ａ，１０Ｂからの無線フレーム同士の衝突及び無線通信装置１０Ｃ，１０Ｄからの無線フレーム同士の衝突が回避されるため、対向側で無線フレームを受信でき、両系現用状態を解消することができる。 Further, in the present embodiment, when a failure occurs in the wireless line and the wireless communication devices 10A and 10B are alternately wirelessly transmitted at the transmission timing of the wireless frames of the wireless communication devices 10A and 10B when the state is shifted to the active state of both systems. It is predetermined to transmit the frame. Similarly, the wireless frame transmission timings of the wireless communication devices 10C and 10D are determined in advance so that the wireless communication devices 10C and 10D alternately transmit wireless frames. Therefore, after the failure of the wireless line is recovered, collision between the wireless frames from the wireless communication devices 10A and 10B and collision between the wireless frames from the wireless communication devices 10C and 10D can be avoided, so that the wireless frame can be received on the opposite side. Both systems can be resolved.
　また、本実施形態においては、無線通信装置１０Ａ～１０Ｄは、障害の発生を検出した場合は、装置ＩＤをＲＤＩフレームに多重して送信する。したがって、障害発生のアラームを、対向側の無線通信装置１０に通知することができるという効果が得られる。 In this embodiment, when the occurrence of a failure is detected, the wireless communication devices 10A to 10D multiplex and transmit the device ID in the RDI frame. Therefore, it is possible to notify the opposite-side radio communication device 10 of an alarm indicating the occurrence of a failure.
　以上、実施形態を参照して本願発明を説明したが、本願発明は上記実施形態に限定されものではない。本願発明の構成や詳細には、本願発明のスコープ内で当業者が理解し得る様々な変更をすることができる。例えば、上記実施形態によれば、無線通信装置１０Ａ～１０Ｄの外部に専用のコントローラを設ける必要がなくなるため、無線通信装置１０Ａ～１０Ｄを、Ｌ２ＳＷ２１，２２から分離して配置することができるようになる。そのため、図３に示された無線通信システムの構成要素のうちＬ２ＳＷ２１，２２以外の構成要素を、屋外に配置する構成とすることができる。 As mentioned above, although this invention was demonstrated with reference to embodiment, this invention is not limited to the said embodiment. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention. For example, according to the above-described embodiment, it is not necessary to provide a dedicated controller outside the radio communication devices 10A to 10D, so that the radio communication devices 10A to 10D can be arranged separately from the L2SWs 21 and 22. Become. Therefore, it can be set as the structure which arrange | positions components other than L2SW21 and 22 among the components of the radio | wireless communications system shown by FIG. 3 outdoors.
　この出願は、２０１５年２月１８日に出願された日本出願特願２０１５－０２９３１６を基礎とする優先権を主張し、その開示の全てをここに取り込む。 This application claims priority based on Japanese Patent Application No. 2015-029316 filed on Feb. 18, 2015, the entire disclosure of which is incorporated herein.
　１０Ａ～１０Ｄ　無線通信装置
　１０１　無線送信部
　１０２　無線受信部
　１０３　切替制御部
　１０４　光受信部
　１０５　無線フレーム多重部
　１０６　無線フレーム抽出部
　１０７　光送信部
　２１，２２　Ｌ２ＳＷ
　３１～３４　光カプラ
　４１，４２　　ハイブリッド 10A to 10D Wireless communication device 101 Wireless transmission unit 102 Wireless reception unit 103 Switching control unit 104 Optical reception unit 105 Radio frame multiplexing unit 106 Radio frame extraction unit 107 Optical transmission unit 21, 22 L2SW
31-34 Optical coupler 41, 42 Hybrid

Claims (17)

  1. 　現用系又は予備系となる第１及び第２の無線通信装置と、
    　前記第１及び第２の無線通信装置と無線回線を介して対向して配置され、現用系又は予備系となる第３及び第４の無線通信装置と、を備え、
    　前記第１～第４の無線通信装置の各々は、
    　自装置が現用系である状況では、前記無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況に基づいて、前記対向側で現用系となる無線通信装置を指示する切替指示を前記対向側の現用系及び予備系の無線通信装置に送信し、
    　前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする、無線通信システム。     A first and second wireless communication device to be an active system or a standby system;
    The first and second wireless communication devices are arranged opposite to each other via a wireless line, and are provided with third and fourth wireless communication devices serving as active or standby systems,
    Each of the first to fourth wireless communication devices includes:
    In the situation where the own device is the active system, the wireless communication device that is the active system on the opposite side is determined based on the failure occurrence status of the active wireless communication device on the opposite side that faces the own device via the wireless line. Send a switching instruction to instruct the active and standby radio communication apparatuses on the opposite side;
    A wireless communication system in which the own apparatus is used as a working system or a standby system based on the switching instruction received from the working wireless communication apparatus on the opposite side.
  2. 　前記第１～第４の無線通信装置の各々は、自装置が現用系である状況で、前記対向側の現用系の無線通信装置に障害が発生したことを検出した場合、該障害が予め設定された時間内に復旧しなければ、前記対向側の予備系の無線通信装置を現用系の無線通信装置として指示する前記切替指示を送信する、請求項１に記載の無線通信システム。 When each of the first to fourth wireless communication apparatuses detects that a failure has occurred in the opposite-side active wireless communication apparatus in a situation where the own apparatus is an active system, the failure is set in advance. 2. The wireless communication system according to claim 1, wherein the switching instruction is transmitted to instruct the opposite standby wireless communication apparatus as an active wireless communication apparatus if the recovery is not performed within a predetermined time.
  3. 　前記第１～第４の無線通信装置の各々は、自装置が予備系である状況で、前記無線回線に障害が発生したことを検出した場合、該障害が予め設定された時間内に復旧しなければ、自装置を現用系とし、自装置が現用系である状況で、前記無線回線に障害が発生したことを検出した場合、自装置を現用系のままとし、
    　前記第１及び第２の無線通信装置は、前記無線回線に障害が発生した場合における前記切替指示の送信タイミングが、前記切替指示を交互に送信するよう予め決められており、また、前記第３及び第４の無線通信装置は、前記無線回線に障害が発生した場合における前記切替指示の送信タイミングが、前記切替指示を交互に送信するよう予め決められている、請求項１又は２に記載の無線通信システム。     When each of the first to fourth wireless communication devices detects that a failure has occurred in the wireless line in a situation where the device is a standby system, the failure is recovered within a preset time. Otherwise, if the own device is the working system, and when the own device is the working system and it detects that a failure has occurred in the wireless line, the own device remains the working system,
    In the first and second wireless communication apparatuses, the transmission timing of the switching instruction when a failure occurs in the wireless line is determined in advance so as to alternately transmit the switching instruction, and the third And the fourth wireless communication device according to claim 1 or 2, wherein a transmission timing of the switching instruction when a failure occurs in the wireless line is determined in advance to alternately transmit the switching instruction. Wireless communication system.
  4. 　前記第１～第４の無線通信装置の各々は、前記無線回線に発生した障害が復旧したことを検出した場合、以降に前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする、請求項３に記載の無線通信システム。 When each of the first to fourth wireless communication devices detects that a failure that has occurred in the wireless line has been recovered, the first to fourth wireless communication devices are based on the switching instruction received from the opposite-side active wireless communication device thereafter. The wireless communication system according to claim 3, wherein the own apparatus is an active system or a standby system.
  5. 　前記第１～第４の無線通信装置の各々は、
    　前記対向側の現用系及び予備系の無線通信装置に前記切替指示を送信する無線送信部と、前記対向側の現用系の無線通信装置から前記切替指示を受信する無線受信部と、を備え、
    　自装置が現用系である状況で、自装置の前記無線受信部に障害が発生したことを検出した場合、該障害を通知するための特定のフレームにて前記切替指示を送信し、
    　前記対向側の現用系の無線通信装置から前記特定のフレームにて前記切替指示が受信されると、前記対向側の現用系の無線通信装置にて障害が発生したと判断する、請求項１から４のいずれか１項に記載の無線通信システム。     Each of the first to fourth wireless communication devices includes:
    A radio transmission unit that transmits the switching instruction to the active and standby radio communication devices on the opposite side, and a radio reception unit that receives the switching instruction from the active radio communication device on the opposite side,
    When it is detected that a failure has occurred in the wireless reception unit of the own device in a situation where the own device is an active system, the switching instruction is transmitted in a specific frame for notifying the failure,
    2. When the switching instruction is received in the specific frame from the opposite-side active wireless communication device, it is determined that a failure has occurred in the opposite-side active wireless communication device. The wireless communication system according to any one of 4.
  6. 　前記第１～第４の無線通信装置の各々は、
    　前記対向側の現用系及び予備系の無線通信装置に前記切替指示を送信する無線送信部と、前記対向側の現用系の無線通信装置から前記切替指示を受信する無線受信部と、を備え、
    　前記対向側の現用系の無線通信装置から前記切替指示を最後に受信してから予め設定された時間が経過し、かつ自装置の前記無線受信部に障害が発生していない場合、前記対向側の現用系の無線通信装置にて障害が発生したと判断する、請求項１から４のいずれか１項に記載の無線通信システム。     Each of the first to fourth wireless communication devices includes:
    A radio transmission unit that transmits the switching instruction to the active and standby radio communication devices on the opposite side, and a radio reception unit that receives the switching instruction from the active radio communication device on the opposite side,
    When the preset time has elapsed since the switching instruction was last received from the active wireless communication device on the opposite side, and no failure has occurred in the wireless reception unit of the own device, the opposite side 5. The wireless communication system according to claim 1, wherein it is determined that a failure has occurred in the active wireless communication device.
  7. 　前記第１～第４の無線通信装置の各々は屋外に配置される、請求項１から６のいずれか１項に記載の無線通信システム。 The wireless communication system according to any one of claims 1 to 6, wherein each of the first to fourth wireless communication devices is disposed outdoors.
  8. 　他の無線通信装置と冗長に構成され、現用系又は予備系となる無線通信装置であって、
    　自装置が現用系である状況では、無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況に基づいて、前記対向側で現用系となる無線通信装置を決定する切替制御部と、
    　自装置が現用系である状況では、前記切替制御部が決定した、前記対向側で現用系となる無線通信装置を指示する切替指示を前記対向側の現用系及び予備系の無線通信装置に送信する無線送信部と、
    　前記対向側の現用系の無線通信装置から前記切替指示を受信する無線受信部と、を備え、
    　前記切替制御部は、前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする、無線通信装置。     A wireless communication device configured to be redundant with other wireless communication devices and serving as a working or standby system,
    In the situation where the own device is the active system, the wireless communication device to be the active system is determined on the opposite side based on the failure occurrence status of the active system wireless communication device on the opposite side facing the own device via the wireless line A switching control unit,
    In the situation where the own apparatus is the active system, the switching control unit determines the switching instruction for instructing the radio communication apparatus to be the active system on the opposite side to the active and standby radio communication apparatuses on the opposite side A wireless transmitter to
    A wireless receiving unit that receives the switching instruction from the active wireless communication device on the opposite side,
    The switching control unit is a wireless communication apparatus in which the own apparatus is set as an active system or a standby system based on the switching instruction received from the opposite-side active wireless communication apparatus.
  9. 　前記無線送信部は、自装置が現用系である状況で、前記対向側の現用系の無線通信装置に障害が発生したことを検出した場合、該障害が予め設定された時間内に復旧しなければ、前記対向側の予備系の無線通信装置を現用系の無線通信装置として指示する前記切替指示を送信する、請求項８に記載の無線通信装置。 When the wireless transmission unit detects that a failure has occurred in the opposite-side active wireless communication device in a situation where the own device is an active system, the failure must be recovered within a preset time. 9. The wireless communication apparatus according to claim 8, wherein the switching instruction is transmitted to instruct the opposite standby wireless communication apparatus as an active wireless communication apparatus.
  10. 　前記切替制御部は、自装置が予備系である状況で、前記無線回線に障害が発生したことを検出した場合、該障害が予め設定された時間内に復旧しなければ、自装置を現用系とし、自装置が現用系である状況で、前記無線回線に障害が発生したことを検出した場合、自装置を現用系のままとし、
    　前記無線送信部は、前記無線回線に障害が発生した場合における前記切替指示の送信タイミングが、自装置と前記他の無線通信装置とで前記切替指示を交互に送信するよう予め決められている、請求項８又は９に記載の無線通信装置。     When the switching control unit detects that a failure has occurred in the wireless line in a situation where the own device is a standby system, the switching control unit determines that the own device is not in the active system unless the failure is recovered within a preset time. In the situation where the own device is the active system, if it detects that a failure has occurred in the wireless line, leave the own device as the active system,
    In the wireless transmission unit, the transmission timing of the switching instruction when a failure occurs in the wireless line is determined in advance to alternately transmit the switching instruction between the own device and the other wireless communication device, The wireless communication apparatus according to claim 8 or 9.
  11. 　前記切替制御部は、前記無線回線に発生した障害が復旧したことを検出した場合、以降に前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする、請求項１０に記載の無線通信装置。 When the switching control unit detects that the failure that has occurred in the wireless line has been recovered, the switching control unit subsequently sets the own device as the active system or based on the switching instruction received from the opposite-side active wireless communication device. The wireless communication apparatus according to claim 10, wherein the wireless communication apparatus is a standby system.
  12. 　前記無線送信部は、自装置が現用系である状況で、前記無線受信部に障害が発生したことを検出した場合、該障害を通知するための特定のフレームにて前記切替指示を送信し、
    　前記切替制御部は、前記対向側の現用系の無線通信装置から前記特定のフレームにて前記切替指示が受信されると、前記対向側の現用系の無線通信装置にて障害が発生したと判断する、請求項８から１１のいずれか１項に記載の無線通信装置。     When the wireless transmission unit detects that a failure has occurred in the wireless reception unit in a situation where the own device is an active system, the wireless transmission unit transmits the switching instruction in a specific frame for notifying the failure,
    When the switching instruction is received in the specific frame from the opposite-side active wireless communication device, the switching control unit determines that a failure has occurred in the opposite-side active wireless communication device. The wireless communication apparatus according to any one of claims 8 to 11.
  13. 　前記切替制御部は、前記対向側の現用系の無線通信装置から前記切替指示を最後に受信してから予め設定された時間が経過し、前記無線受信部に障害が発生していない場合、前記対向側の現用系の無線通信装置にて障害が発生したと判断する、請求項８から１２のいずれか１項に記載の無線通信装置。 The switching control unit, when a preset time has elapsed since the switching instruction was last received from the opposite-side active wireless communication device, and no failure has occurred in the wireless receiving unit, The wireless communication apparatus according to claim 8, wherein it is determined that a failure has occurred in the active wireless communication apparatus on the opposite side.
  14. 　前記無線通信装置は屋外に配置される、請求項８から１３のいずれか１項に記載の無線通信装置。 The wireless communication device according to any one of claims 8 to 13, wherein the wireless communication device is disposed outdoors.
  15. 　他の無線通信装置と冗長に構成され、現用系又は予備系となり、無線回線を介して信号を送信する無線通信装置であって、
    　自装置が現用系である状況では、前記無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況を検知して前記障害発生状況に基づいて前記対向側で現用系となる無線通信装置を決定する切替制御部と、
    　前記無線回線を介して、前記決定した無線通信装置を示す信号を送信する無線送信部と、を備える無線通信装置。     A wireless communication device that is configured redundantly with other wireless communication devices, becomes an active system or a standby system, and transmits a signal via a wireless line,
    In a situation where the own apparatus is the active system, the failure occurrence status of the active wireless communication apparatus on the opposite side facing the own apparatus is detected via the wireless line, and the active side is active on the opposite side based on the failure occurrence status. A switching control unit for determining a wireless communication device to be a system;
    A wireless communication device comprising: a wireless transmission unit that transmits a signal indicating the determined wireless communication device via the wireless line.
  16. 　無線通信システムによる無線通信方法であって、
    　現用系又は予備系となる第１及び第２の無線通信装置と、
    　前記第１及び第２の無線通信装置と無線回線を介して対向して配置され、現用系又は予備系となる第３及び第４の無線通信装置と、を設け、
    　前記第１～第４の無線通信装置の各々が、自装置が現用系である状況では、前記無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況に基づいて、前記対向側で現用系となる無線通信装置を指示する切替指示を前記対向側の現用系及び予備系の無線通信装置に送信し、
    　前記第１～第４の無線通信装置の各々が、前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする、無線通信方法。     A wireless communication method using a wireless communication system,
    A first and second wireless communication device to be an active system or a standby system;
    The first and second wireless communication devices are arranged to face each other via a wireless line, and the third and fourth wireless communication devices serving as a working system or a standby system are provided,
    In the situation where each of the first to fourth wireless communication apparatuses is the active system, the first to fourth wireless communication apparatuses are based on the failure occurrence state of the active wireless communication apparatus on the opposite side facing the own apparatus via the wireless line. A switching instruction for instructing the wireless communication device to be the active system on the opposite side is transmitted to the active and standby wireless communication devices on the opposite side,
    A wireless communication method in which each of the first to fourth wireless communication devices sets its own device as an active or standby system based on the switching instruction received from the opposite-side active wireless communication device.
  17. 　他の無線通信装置と冗長に構成され、現用系又は予備系となる無線通信装置による無線通信方法であって、
    　自装置が現用系である状況では、無線回線を介して自装置と対向する対向側の現用系の無線通信装置の障害発生状況に基づいて、前記対向側で現用系となる無線通信装置を指示する切替指示を前記対向側の現用系及び予備系の無線通信装置に送信し、
    　前記対向側の現用系の無線通信装置から受信した前記切替指示に基づいて、自装置を現用系又は予備系とする、無線通信方法。     A wireless communication method by a wireless communication device that is configured redundantly with another wireless communication device and is an active or standby system,
    In the situation where the own device is the active system, the radio communication device that is the active system is instructed on the opposite side based on the failure occurrence status of the active radio communication device on the opposite side that faces the own device via the wireless line To transmit the switching instruction to the active and standby radio communication devices on the opposite side,
    A wireless communication method in which the own apparatus is used as a working system or a standby system based on the switching instruction received from the working wireless communication apparatus on the opposite side.
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